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                                                                    EXHIBIT 10.8


                                 LEASE AGREEMENT


         THIS LEASE AGREEMENT is made this 31st day of March 1995, between
Security Capital Industrial Trust, a Maryland real estate investment trust
("Landlord"), and the Tenant named below.



<TABLE>
<S>                                 <C>
TENANT:                             Crystal Semiconductor Corporation and Cirrus
                                    Logic, Inc.

TENANT'S REPRESENTATIVE,            Mr. John McGovern, Vice President of Finance
ADDRESS, AND PHONE NO.:             4210 S. Industrial Drive, Austin, Texas 78744
                                    (512-445-7222)


PREMISES:                           Approximately 44,000 square feet in the
                                    Building as shown on Exhibit A until January
                                    1, 1996, with the Premises increasing to
                                    88,000 square feet in the Building as shown
                                    on Exhibit A after January 1, 1996. Tenant
                                    will have reasonable rights of access to the
                                    portion of the Building that is not part of
                                    the Premises prior to January 1, 1996 for
                                    planning, construction, installation and
                                    temporary storage.



PROJECT:                            The portion of Southpark Corporate Center
                                    located on the land legally described as
                                    Lots 13, 14, and 15, Ben White Business
                                    Park, a subdivision in Austin, Travis
                                    County, Texas, according to the map or plat
                                    thereof recorded in Book 84, Pages 88A-88B
                                    of the Plat Records of Travis County, Texas,
                                    as shown on Exhibit A-1.

BUILDING (IF NOT THE
SAME AS THE PROJECT):               Southpark Corporate Center 3, located on the
                                    land legally described as Lots 13, 14, and
                                    15, Ben White Business Park, a subdivision
                                    in Austin, Travis County, Texas, according
                                    to the map or plat thereof recorded in Book
                                    84, Pages 88A-88B of the Plat Records of
                                    Travis County, Texas.


TENANT'S PROPORTIONATE SHARE
OF BUILDING:                        50% until January 1, 1996 and 100% thereafter.

TENANT'S PROPORTIONATE SHARE
OF PROJECT:                         25% until January 1, 1996 and 50% thereafter.

LEASE TERM:                         Beginning on the Commencement Date and ending
                                    on the last day of the 120th full calendar
                                    month thereafter.

COMMENCEMENT DATE:                  July 1, 1995


MONTHLY BASE RENT:

                         Period                                     Rent
                         ------                                     ----

         Commencement Date - December 31, 1995                   $20,863.33

         January 1, 1996 - until the last day of the
         60th full calendar month after the
         Commencement Date                                       $41,726.67

         First day of the 61st full calendar month
         after the Commencement Date until the last day
         of the 120th full calendar month after the
         Commencement Date                                       $46,273.33



ESTIMATED MONTHLY OPERATING         1. Utilities:             N/A
EXPENSE PAYMENTS: (estimates
only and subject to                 2. Common Area Charges:   $1,320.00
adjustment to actual costs
and expenses according to           3. Taxes:                 $6,966.67
the provisions of this
Lease)                              4. Insurance:             $  293.33

                                    5. Others:                $1,320.00

TOTAL ESTIMATED MONTHLY OPERATING
EXPENSE PAYMENTS:                                                     $9,900.00

SECURITY DEPOSIT:                   None.

BROKER:                             Commercial Industrial Properties as agent for the
                                    Tenant, and Oxford Commercial as agent for the
                                    Landlord




ADDENDA:                            Exhibit A - Description of Premises, Building and
                                    Building 4; Exhibit A-1 - Description of Project;
                                    Exhibit B - Construction Addendum; Exhibit B-1 -
                                    Landlord's Improvements; Exhibit B-2 - Tenant
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                                    Floor Plan; Rider 1 to Exhibit B-1; Addendum
                                    1 to Rider 1 of Exhibit B-1; Exhibit C -
                                    Rules and Regulations; Addendum D - Storage,
                                    Generation and Use of Hazardous Materials;
                                    Exhibit D-l - List of Permitted Hazardous
                                    Materials, Exhibit D-2 - Description of
                                    Proposed Use and Processes; Addendum E -
                                    Landlord's Environmental Covenants; Exhibit
                                    F - Sign Specifications for Monument Sign;
                                    Exhibit F-1 - Sign Specifications for
                                    Building Sign; Addendum G - Assignment and
                                    Subletting; Exhibit H - List of other
                                    existing tenants in Project

         1. GRANTING CLAUSE. In consideration of the obligation of Tenant to pay
rent as herein provided and in consideration of the other terms, covenants, and
conditions hereof, Landlord leases to Tenant, and Tenant takes from Landlord,
the Premises, to have and to hold for the Lease Term, subject to the terms,
covenants and conditions of this Lease.

         2. ACCEPTANCE OF PREMISES. Tenant accepts the Premises in its condition
as of the date hereof, subject to all applicable laws, ordinances, and
regulations; provided, however, Landlord agrees to install the tenant
improvements (the "Initial Tenant Improvements") described in the Construction
Addendum, if any, attached hereto. Tenant acknowledges that Landlord has made no
representation or warranty as to the suitability of the Premises for the conduct
of Tenant's business, and Tenant waives any implied warranty that the Premises
are suitable for Tenant's intended purposes. The taking of possession of the
Premises shall be conclusive evidence that Tenant accepts the Premises and that
the Premises were in good condition at the time possession was taken except for
any punchlist items agreed to in writing by Landlord and Tenant, and except for
latent defects. In no event shall Landlord be liable for any defects in the
Premises or for any limitation on its use, except for latent defects.

         3. USE. The Premises shall be used only for the purpose of designing,
engineering, testing, demonstrating, producing, receiving, storing, shipping,
manufacturing of semiconductor integrated circuits and selling (but limited to
wholesale sales) products, materials and merchandise made and/or distributed by
Tenant and for such other lawful purposes as may be incidental thereto. Tenant
shall not conduct or give notice of any auction, liquidation, or going out of
business sale on the Premises. Tenant will use the Premises in a careful, safe
and proper manner and will not commit waste thereon.

                  Tenant, at its sole expense, shall comply with all laws
(including, without limitation, Environmental Requirements, as defined herein,
and laws regarding access for handicapped or disabled persons), ordinances and
regulations, and all declarations, covenants, and restrictions, applicable to
Tenant's use or occupation of the Premises, and with all governmental orders and
directives of public officers which impose any duty or restriction with respect
to the use or occupation of the Premises. Outside storage, including without
limitation, storage of trucks and other vehicles, is prohibited without
Landlord's prior written consent. Tenant shall cause additional improvements to
the Premises done after the Commencement Date to comply with the Americans with
Disabilities Act or similar state statutes or local ordinances or any
regulations promulgated thereunder, all as may be amended from time to time (the
"ADA"), and Tenant shall cause the Premises (and to the extent required by the
Premises, the Project) to hereafter comply with the ADA. Notwithstanding the
foregoing, as of the Commencement Date, Landlord shall make the exterior of the
Building and Landlord's Improvements (as defined on Exhibit B) and other work to
be performed and described on Exhibit B in compliance with the ADA. Landlord
will cause the exterior of the Premises to be in compliance with future changes
as required by state or federal agencies.

                  Tenant shall not permit any objectionable or unpleasant odors,
smoke, dust, gas, noise, or vibrations to emanate from the Premises in violation
of law, or take any other action that would constitute a nuisance or would
unreasonably disturb, interfere with, or endanger Landlord or any other tenants
of the Project. Tenant will not use or permit the Premises to be used for any
purpose or in any manner that would void Tenant's or Landlord's insurance. If
any increase in the cost of any insurance on the Premises or the Project is
caused by Tenant's use of the Premises, or because Tenant vacates the Premises,
then Tenant shall pay the amount of such increase to Landlord.

         4. BASE RENT. Tenant shall pay Base Rent in the amount set forth above.
The first month's Base Rent, and the first monthly installment of estimated
Operating Expenses (as hereafter defined) shall be due and payable on the date
hereof, and Tenant promises to pay to Landlord in advance, without demand,
deduction or set-off, monthly installments of Base Rent on or before the first
day of each calendar month succeeding the Commencement Date. Payments of Base
Rent for any fractional calendar month shall be prorated. All payments required
to be made by Tenant to Landlord hereunder shall be payable at such address as
Landlord may specify from time to time by written notice delivered in
accordance herewith. The obligation of Tenant to pay Base Rent and other sums to
Landlord and the obligations of Landlord under this Lease are independent
obligations. Tenant shall have no right at any time to abate, reduce, or set-off
any rent due hereunder except where expressly provided in this Lease. Tenant
waives and releases all statutory liens and offset rights as to rent.

                  If Tenant is delinquent in any monthly installment of Base
Rent beyond 5 days after the due date thereof, and after notice as provided
below, Tenant shall pay to Landlord on demand a late charge equal to 5 percent
of such delinquent sum, to help defray the additional costs and expenses to
Landlord for processing such late payment. Tenant shall not be obligated to pay
the late charge until Landlord has given Tenant 5 days written notice of the
delinquent payment (which may be given at any time during the delinquency);
provided, however, that such notice shall not be required more than twice in any
12-month period or five times over the term of the Lease. The provision of such
late charge shall be in addition to all of Landlord's other rights and remedies
hereunder or at law and shall not be construed as a penalty or as limiting
Landlord's remedies in any manner.

         5. SECURITY DEPOSIT. [Intentionally Omitted]

         6. OPERATING EXPENSE PAYMENTS. During each month of the Lease Term, on
the same date that Base Rent is due, Tenant shall pay Landlord an amount equal
to 1/12 of the annual cost, as estimated by Landlord from time to time, of
Tenant's Proportionate Share (hereinafter defined) of Operating Expenses for the
Project. Payments thereof for any fractional calendar month shall be prorated.
The term "Operating Expenses" means all costs and expenses incurred by Landlord
with the respect to the ownership, maintenance, and operation of the Project
including, but not limited to costs of Taxes (hereinafter defined) and
reasonable fees payable to tax consultants and attorneys for consultation and
contesting taxes; insurance; utilities; maintenance and repair of certain
portions of the Project, including mowing, landscaping, exterior lighting and
other items described in Paragraph 11 below; painting (except that Landlord
shall be required to provide one quality exterior painting of the Premises for
each five years of occupancy by Tenant at Landlord's expense); amounts paid to
contractors and subcontractors for work or services performed in connection with
any of the foregoing; charges or assessments of any association to which the
Project is subject; property management fees payable to a property manager,
including any affiliate of Landlord, but in no event will the property
management fee expense exceed 3% of the gross rents received by Landlord from
Tenant, or if there is no property manager, an administration fee of 3% of the
gross rents received by Landlord. Operating Expenses do not include costs or
expenses or depreciation or amortization for capital repairs and capital
replacements required to be made by Landlord under Paragraph 10 of this Lease,
debt service under mortgages or ground rent under ground leases, costs of
restoration to the extent of net insurance proceeds received by Landlord with
respect thereto, leasing commissions, or the costs of renovating space for
tenants. Tenant shall be entitled from time to time upon request to receive
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Landlord as may be necessary in Tenant's reasonable judgment to support and
evidence Operating Expenses and the calculation of Tenant's Proportionate Share.

                  If Tenant's total payments for any year are less than Tenant's
Proportionate Share of actual Operating Expenses for such year, Tenant shall pay
the difference to Landlord within 30 days after demand and receipt of a
reconciliation of the difference. If the total payments of Tenant for any year
are more than Tenant's Proportionate Share of actual Operating Expenses for such
year, Landlord shall retain such excess and credit it against Tenant's next
payments, and provide Tenant with a reconciliation of the difference. For
purposes of calculating Tenant's Proportionate Share of Operating Expenses, a
year shall mean a calendar year except the first year, which shall begin on the
Commencement Date, and the last year, which shall end on the expiration of this
Lease. With respect to Operating Expenses which Landlord allocates to the entire
Project, Tenant's "Proportionate Share" shall be the percentage set forth on the
first page of this Lease as Tenant's Proportionate Share of the Project as
reasonably adjusted by Landlord in the future for changes in the physical size
of the Premises or the Project; and, with respect to Operating Expenses which
Landlord allocates only to the Building, Tenant's "Proportionate Share" shall be
the percentage set forth on the first page of this Lease as Tenant's
Proportionate Share of the Building as reasonably adjusted by Landlord in the
future for changes in the physical size of the Premises or the Building.
Landlord may equitably increase Tenant's Proportionate Share for any item of
expense or cost reimbursable by Tenant that relates to a repair, replacement, or
service that benefits only the Premises or only a portion of the Project that
includes the Premises or that varies with the occupancy of the Project. The
estimated Operating Expenses for the Premises set forth on the first page of
this Lease are only estimates, and Landlord makes no guaranty or warranty that
such estimates will be accurate.

                  Notwithstanding the above, Tenant shall not be obligated to
pay for controllable Operating Expenses in any year to the extent they have
increased by more than five percent (5%) per annum on a cumulative basis from
the first calendar year during the Lease Term. For purposes of this Section,
"controllable Operating Expenses" shall mean those Operating Expenses reasonably
within the control of Landlord. In no event, however, shall Taxes, insurance
premiums or utility costs be deemed controllable Operating Expenses.
Controllable Operating Expenses shall be determined on an aggregate basis and
not on an individual basis, and the cap on controllable Operating Expenses shall
be determined on Operating Expense as they have been adjusted for vacancy or
usage pursuant to the terms of the Lease.

         7. UTILITIES. Tenant shall pay for all water, gas, electricity, heat,
light, power, telephone, sewer, sprinkler services, refuse and trash collection,
and other utilities and services used on the Premises, all maintenance charges
for utilities, and any storm sewer charges or other similar charges for
utilities imposed by any governmental entity or utility provider, together with
any taxes, penalties, surcharges or the like pertaining to Tenant's use of the
Premises. Landlord shall have the right to cause at Tenant's expense any of said
services to be separately metered or charged directly to Tenant by the provider.
Tenant shall pay its share of all charges for jointly metered utilities based
upon consumption, as reasonably determined by Landlord. Landlord shall not be
liable for any interruption or failure of utilities or any other service to the
Premises and no such interruption or failure shall result in the abatement of
rent hereunder. Tenant agrees to limit use of water and sewer for normal
restroom use and nothing herein contained shall impose upon Landlord any duty to
provide sewer or water usage for other than normal restroom usage.

         8. TAXES. Landlord agrees to pay its Proportionate Share of all taxes,
assessments and governmental charges of any kind and nature (collectively
referred to as "Taxes") that accrue against the Project during the Lease Term,
which shall be included as part of the Operating Expenses charged to Tenant
hereunder, provided Landlord shall have the right to contest by appropriate
legal proceedings the amount, validity, or application of any Taxes or liens
thereof. All capital levies or other taxes assessed or imposed on Landlord upon
the rents payable to Landlord under this Lease and any excise, transaction,
sales tax, assessment, levy or charge measured by or based, in whole or in part,
upon such rents from the Premises and/or the Project or any portion thereof
shall be paid by Tenant to Landlord monthly in estimated installments as
additional rent (but only to the extent customarily charged by Landlord to other
tenants); provided, however, in no event shall Tenant be liable for any net
income or franchise taxes. If any such tax or excise is levied or assessed
directly against Tenant, then Tenant shall be responsible for and shall pay the
same at such times and in such manner as the taxing authority shall require.
Landlord agrees to cause the Project to be a separate tax parcel for
governmental billing purposes. Tenant shall be liable for all taxes levied or
assessed against any personal property or fixtures placed in the Premises,
whether levied or assessed against Landlord or Tenant.

         9. INSURANCE. Landlord shall maintain fire and extended coverage
insurance covering the replacement coat of the Project, subject to customary
deductibles. Landlord may, but is not obligated to, maintain such other
insurance and additional coverages as it may reasonably deem necessary,
including, but not limited to, commercial liability insurance and rent loss
insurance. All such insurance shall be included as part of the Operating
Expenses charged to Tenant hereunder. The Project may be included in a blanket
policy (in which case the cost of such insurance allocable to the Project will
be determined by Landlord based upon the insurer's cost calculations). Tenant
shall also reimburse Landlord for any increased premiums or additional insurance
which Landlord reasonably deems necessary as a result of Tenant's use of the
Premises. The fire and extended coverage policy shall not be cancellable unless
20 days prior written notice shall have been given to Tenant. A certificate
evidencing such policy and tenant's notice rights thereunder shall be provided
to Tenant on or before the Commencement Date, and upon any insurance renewal
date. Tenant may maintain such fire and extended coverage upon any failure by
Landlord to maintain such coverage.

                  Tenant, at its expense, shall maintain during the Lease Term a
policy or policies of: fire and extended coverage insurance covering the
replacement cost of all property and improvements, installed or placed in the
Premises by Tenant at Tenant's expense; worker's compensation insurance with no
less than the minimum limits required by law; employer's liability insurance
with such limits as required by law; commercial liability insurance, with
liability limits of not less than $2,000,000 combined single limit per
occurrence (together with such umbrella coverage as Landlord may reasonably
require) for property damage, personal injuries, or deaths of persons occurring
in or about the Premises; provided, however, that Landlord may from time to time
require reasonable increases in any such limits. The commercial liability
policies shall name Landlord as an additional insured, insure on an occurrence
and not a claims-made basis, be issued by insurance companies which are
reasonably acceptable to Landlord, not be cancelable unless 20 days prior
written notice shall have been given to Landlord, and provide primary coverage
to Landlord (any policy issued to Landlord providing duplicate or similar
coverage shall be deemed excess over Tenant's policies). Such policies or
certificates thereof shall be delivered to Landlord by Tenant upon commencement
of the Lease Term and upon each renewal of said insurance.

                  The fire and extended coverage insurance obtained by Landlord
and Tenant shall include a waiver of subrogation by the insurers and all rights
based upon an assignment from its insured, against Landlord or Tenant, their
officers, directors, employees, managers, agents, invitees and contractors, in
connection with any loss or damage thereby insured against. Neither party nor
its officers, directors, employees, managers, agents, invitees or contractors
shall be liable to the other for loss or damage caused by any risk covered by
fire and extended coverage property insurance, and each party waives any claims
against the other party, and its officers, directors, employees, managers,
agents, invitees and contractors for such loss or damage. The failure of a party
to insure its property shall not void this waiver.


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         10. LANDLORD'S REPAIRS. Landlord shall maintain, at its expense, the
structural soundness of the roof, foundation, and exterior walls of the building
of which the Premises are a part and all other parts of the Premises that are
stated to be the responsibility of the Landlord hereunder in good repair,
reasonable wear and tear and damages caused by Tenant (if not covered by the
insurance required to be carried by Landlord pursuant to Section 9 hereof)
excluded. The term "walls" as used in this Paragraph 10 shall not include
windows, glass or plate glass, doors or overhead doors, special store fronts,
dock bumpers, dock plates or levelers, or office entries, unless any of the same
are damaged as a result of a structural problem (other than structural problems
that are uninsured and caused by Tenant). Tenant shall immediately give Landlord
written notice of any repair required by Landlord pursuant to this Paragraph 10,
after which Landlord shall have a reasonable opportunity to repair.

         11. TENANT'S REPAIRS. Landlord shall maintain in good repair and
condition all parts of the Premises and the parking areas, driveways and
landscape and grounds surrounding the Premises. Such maintenance shall be at
Tenant's cost and expense except as to those repairs for which Landlord is
responsible under Paragraph 10, and except for the paving of the parking areas
and the painting of the exterior walls of the Premises, which shall be paid for
by Landlord; provided, however, if Tenant leases less than the entire Project,
Tenant shall only be responsible for its Proportionate Share of the costs of
maintaining any items outside its Premises. In addition, Tenant shall, at
Tenant's expense maintain the heating and air conditioning and other mechanical
systems and components of the Premises, including lighting, electrical systems,
and plumbing lines and equipment. Tenant, at its own cost and expense shall
enter into and deliver to Landlord one or more maintenance service contracts
reasonably acceptable to Landlord with a contractor(s) reasonably approved by
Landlord for heating and air conditioning. The service and maintenance
contract(s) must include all services reasonably required by Landlord. In the
event Tenant does not so deliver the service contract(s), Landlord shall have
the right to contract for said service without notice to Tenant, and Tenant
shall upon demand reimburse Landlord for the full cost thereof. To the extent
not covered by the insurance Landlord is required to maintain pursuant to
Section 9 hereof, and subject to the provisions of Paragraph 15, Tenant shall
repair and pay for any damage to the Premises or the Project caused by Tenant or
Tenant's employees, agents, or invitees, or caused by Tenant's default
hereunder. Tenant shall in any event pay the amount of any deductible for the
insurance Landlord is required to maintain pursuant to Section 9. Tenant shall
reimburse Landlord for all such costs and expenses in accordance with the
provisions of Paragraph 6 above, except to the extent such repairs are covered
by insurance on the Project under policies naming Landlord as the insured.
Notwithstanding the foregoing, Landlord may at any time assume the maintenance
and repair obligations set forth in this paragraph as they relate to the
Premises, if Landlord determines in its reasonable discretion that such
maintenance and repair obligations are not being satisfactorily performed by
Tenant.

         12. TENANT IMPROVEMENTS AND TRADE FIXTURES. Any material alterations,
additions, or improvements made by or on behalf of Tenant to the Premises
("Tenant Improvements") shall be subject to Landlord's prior written consent,
which shall not be unreasonably withheld, provided that such Tenant Improvements
do not affect any structural, or materially affect any mechanical, plumbing or
electrical systems of the Project. All Tenant Improvements shall comply with
insurance requirements and with applicable laws, ordinances, and regulations,
including, without limitation and to the extent applicable, laws and regulations
regarding removal or alteration of structural or architectural barriers to
handicapped or disabled persons (and Tenant shall construct at its expense any
alteration required by such laws or regulations, as they may be amended). All
Tenant Improvements shall be constructed in a good and workmanlike manner and
only good grades of materials shall be used. All plans and specifications for
any Tenant Improvements shall be submitted to Landlord for its approval, and
Landlord may monitor construction of the Tenant Improvements; and Tenant shall
reimburse Landlord for its reasonable out-of-pocket costs in reviewing plans and
documents and in monitoring construction. Landlord may post on and about the
Premises notices and give notices that Landlord shall not be liable on account
of any damage or claim in connection with such construction, and Tenant shall
provide Landlord with the identities and mailing addresses of all persons
performing work or supplying materials, prior to beginning such construction.
Landlord's right to review plans and specifications and monitor construction
shall be solely for its own benefit, and Landlord shall have no duty to see that
such plans and specifications or construction comply with applicable laws,
codes, rules, or regulations. At Landlord's request, Tenant shall obtain payment
and performance bonds for any Tenant Improvements which bonds shall be delivered
to Landlord prior to commencement of work on the Tenant Improvements and shall
be in form and substance reasonably satisfactory to Landlord. Upon completion of
any Tenant Improvements, Tenant shall deliver to Landlord sworn statements
setting forth the names of all contractors and subcontractors who did work on
the Tenant Improvements and final lien waivers from all such contractors and
subcontractors.

                  Tenant, at its own cost and expense, may erect such shelves,
bins, machinery and trade fixtures (collectively "Trade Fixtures") as it desires
provided that such items do not alter the basic character of the Premises or the
Project, do not overload or damage the same, and may be removed without injury
to the Premises, and provided that the construction, erection, and installation
thereof complies with all applicable governmental laws, ordinances, regulations
and with Landlord's reasonable requirements. Subject to Paragraph 39 below, upon
the expiration of the Lease Term, Tenant shall remove its Trade Fixtures and
shall repair any damage caused by such removal, by the last day of the Lease
Term.

         13. SIGNS. Tenant shall not make any changes to the exterior of the
Premises, install any exterior lights, decorations, balloons, flags, pennants,
banners, or painting, or erect or install any signs, windows or door lettering,
placards, decorations, or advertising media of any type which can be viewed from
the exterior of the Premises, without Landlord's prior written consent which
shall not be unreasonably withheld. Upon vacation of the Premises, Tenant shall
remove all signs and repair, paint, and/or replace the building facia surface to
which its signs are attached. Tenant shall obtain all applicable governmental
permits and approvals for sign and exterior treatments. All signs, decorations,
advertising media, blinds, draperies and other window treatment or bars or other
security installations visible from outside the Premises shall be subject to
Landlord's approval and conform in all respects to Landlord's requirements. A
monument sign containing only the name of the Tenant will be installed, at
Landlord's expense, at the southeast corner of South Industrial Drive and
Commercial Center Drive, provided that such proposed signage complies with all
requirements of the City of Austin. Landlord will also install at its expense a
sign containing the name of the Project at the northeast corner of East St. Elmo
and South Industrial Drive. The specifications for these signs are attached
hereto as Exhibit F and Exhibit F-1.

         14. PARKING. Tenant shall be entitled to park in common with other
tenants of the Project in those areas designated for nonreserved parking.
Landlord may allocate parking spaces among Tenant and other tenants in the
Project if Landlord reasonably determines that such parking facilities are
becoming crowded. Landlord shall not be responsible for enforcing Tenant's
parking rights against any third parties. Tenant may enforce its exclusive
parking rights, and may have improperly parked vehicles towed away. Additional
parking agreements are set forth in Exhibit B, Section 3(D).

         15. FIRE AND CASUALTY DAMAGE. If at any time during the Lease Term, the
Premises or the Project is materially damaged by fire or other casualty,
Landlord shall notify Tenant, within 45 days after such damage, as to the amount
of time Landlord reasonably estimates it will take to repair such damage. If the
amount of time estimated to repair the damage exceeds 4 months after the date of
such notification, either Landlord or Tenant may elect, upon notice to the other
party delivered as soon as practicable but not later than 30 days after
Landlord's notice, to terminate this Lease. If neither party elects to terminate
this Lease or if Landlord estimates that the damage will take 4 months after
the date of such notification or less to repair, Landlord shall promptly repair
and reconstruct the improvements, subject to reasonable


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delays arising from the collection of insurance proceeds or from Force Majeure
events, except that Landlord shall not be required to repair and reconstruct any
fixtures, additions, or other improvements paid for by Tenant; and this Lease
shall remain in full force and effect provided that the Lease Term will be
extended for a time equal to the period beginning on the date the loss or damage
was suffered until the repairs and replacement are completed. Tenant at Tenant's
expense shall promptly perform, subject to delays arising from the collection of
insurance proceeds, all repairs or restoration not required to be done by
Landlord and shall promptly reenter the Premises and commence doing business in
accordance with this Lease. Notwithstanding the foregoing, either party may
terminate this Lease if the improvements are damaged during the last year of the
Lease Term and Landlord reasonably estimates that it will take more than one
month to repair such damage.

                  If Landlord elects to repair and/or reconstruct the damaged
improvements and such improvements are located solely within the Premises,
Tenant shall pay to Landlord the amount of the commercially reasonable
deductible under Landlord's insurance policy (up to $10,000) within 10 days
after presentment of Landlord's invoice. If the damage involves the premises of
other tenants, Tenant shall pay the portion of the deductible in the proportion
that the cost of the repair and replacement of the Premises bears to the total
cost of repair and replacement, as determined by Landlord.

                  If the Premises or a portion thereof is not usable as a result
of damage by fire or other casualty to the Premises or building in which the
Premises are located, and Landlord elects to repair and/or reconstruct the
damaged improvements, Base Rent shall be abated for the period of repair and
reconstruction in the proportion which the area of the Premises which is not
usable by Tenant bears to the total area of the Premises. Such abatement shall
be the sole remedy of Tenant, and to the extent permitted by applicable law, and
except as provided herein, Tenant waives any right to terminate the Lease by
reason of damage or casualty loss.

         16. CONDEMNATION. If any part of the Premises or the Project should be
taken for any public or quasi-public use under governmental law, ordinance, or
regulation, or by right of eminent domain, or by private purchase in lieu
thereof (a "Taking" or "Taken"), and the Taking would prevent or materially
interfere with Tenant's use of the Premises or in Landlord's judgment would
materially interfere with or impair its ownership or operation of the Project,
then upon written notice by Landlord or Tenant this Lease shall terminate and
Base Rent shall be apportioned as of said date. If part of the Premises shall be
Taken, and this Lease is not terminated as provided above, the Base Rent payable
hereunder during the unexpired Lease Term shall be reduced to such extent as may
be fair and reasonable under the circumstances. In the event of any such taking,
Landlord shall be entitled to receive the entire price or award from any such
taking without any payment to Tenant, and Tenant hereby assigns to Landlord
Tenant's interest, if any, in such award. Notwithstanding the foregoing, Tenant
shall have the right to make a separate claim against the condemning authority
(but not Landlord) for such compensation as may be separately awarded or
recoverable by Tenant for any costs of Tenant Improvements paid for by Tenant,
moving expenses, damage to Tenant's Trade Fixtures, and other relocation
benefits as may be allowed by law if a separate award for such items is made to
Tenant.

         17. ASSIGNMENT AND SUBLETTING. Without Landlord's prior written
consent, which shall not be unreasonably withheld pursuant to the standards set
forth on Addendum G attached hereto, Tenant shall not assign this Lease or
sublease the Premises or any part thereof or mortgage, pledge, or hypothecate
its leasehold interest or grant any concession or license within the Premises
and any attempt to do any of the foregoing shall be void and of no effect.
Tenant may assign or sublet the Premises, or any part thereof, to any entity
controlling Tenant, controlled by Tenant or under common control with Tenant (a
"Tenant Affiliate"), without the prior written consent of Landlord. Tenant shall
reimburse Landlord for all of Landlord's reasonable out-of-pocket expenses in
connection with any assignment or sublease.

                  Notwithstanding anything else herein to the contrary, Tenant
may assign or sublease without first obtaining Landlord's consent up to
approximately 22,000 square feet in the Building and up to approximately 22,000
square feet in Building 4 (as defined in Section 39 hereof) provided that the
assignee or sublessee will use their portion of the premises in such a manner as
other buildings owned by Landlord in San Antonio or Austin are being used at the
time of the proposed sublease or assignment. The actual square footage amounts
of preapproved sublets and assignments shall be based on final configurations
for the Building and Building 4.

                  Notwithstanding any assignment or subletting, Tenant and any
guarantor or surety of Tenant's obligations under this Lease shall at all times
remain fully responsible and liable for the payment of the rent and for
compliance with all of Tenant's other obligations under this Lease (regardless
of whether Landlord's approval has been obtained for any such assignments or
sublettings). In the event that the rent due and payable by a sublessee or
assignee (or a combination of the rental payable under such sublease or
assignment plus any bonus or other consideration therefor or incident thereto)
exceeds the rental payable under this Lease, then Tenant shall be bound and
obligated to pay Landlord as additional rent hereunder all such excess rental
and other excess consideration (after deducting its reasonable costs and
expenses associated with each sublease or assignment, including leasing
commissions, and after further deducting all tenant improvement costs associated
with such sublease or assignment, including leasing commissions, and after
further deducting all tenant improvement costs and expenses associated with such
sublease or assignment, as well as real estate taxes, insurance and Operating
Expenses paid by Tenant on account of such space during the term of such
sublease or assignment) within 10 days following receipt thereof by Tenant.

                  If this Lease be assigned or if the Premises be subleased
(whether in whole or in part) or if the Premises be occupied in whole or in part
by anyone other than Tenant, then upon a default by Tenant hereunder Landlord
may collect rent from the assignee, sublessee, or other occupant and, except to
the extent set forth in the preceding paragraph, apply the amount collected to
the next rent payable hereunder; and all such rentals collected by Tenant shall
be held in trust for Landlord and immediately forwarded to Landlord. No such
transaction or collection of rent or application thereof by Landlord, however,
shall be deemed a waiver of these provisions or a release of Tenant from the
further performance by Tenant of its covenants, duties, or obligations
hereunder.

         18. INDEMNIFICATION AND WAIVER. Except for Landlord's negligence and to
the extent permitted by law, Tenant agrees to indemnify, defend and hold
harmless Landlord, and Landlord's agents and employees, from and against any and
all losses, liabilities, damages, costs and expenses (including attorneys' fees)
resulting from claims by third parties for injuries to any person and damage to
or theft or misappropriation or loss of property occurring in or about the
Project and arising from the use and occupancy of the Premises or from any
activity, work, or thing done, permitted or suffered by Tenant in or about the
Premises or due to any other act or omission of Tenant, its subtenants,
assignees, invitees, employees, contractors and agents. The furnishing of
insurance required hereunder shall not be deemed to limit Tenant's obligations
under the provisions of this Paragraph 18.

                  Landlord and its agents and employees shall not be liable for,
and Tenant hereby waives all claims against such parties for, damage to property
sustained by Tenant or damage to property sustained by any person claiming
through Tenant resulting from any accident or occurrence in or upon the Premises
or in or about the Project from any cause whatsoever, including without
limitation, damage caused in whole or in part, directly or indirectly, by the
negligence of Landlord or its agents or employees; provided, however, such
waiver as to property shall only be effective to the extent such property is
reasonably coverable by Tenant's insurance.

         19. INSPECTION AND ACCESS. Landlord and its agents, representatives,
and contractors may enter the Premises during normal business hours (upon prior
notice, except in the case of an emergency) to inspect the Premises and to make
such repairs as may be

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required or permitted pursuant to this Lease and for any other business purpose.
Landlord and Landlord's representatives may enter the Premises during normal
business hours upon prior notice for the purpose of showing the Premises to
prospective purchasers or, during the last year of the Lease Term, to
prospective tenants; in addition, Landlord shall have the right to erect a
suitable sign on the Premises stating the Premises are available to let or that
the Project is available for sale. Tenant may escort any person entering the
Premises pursuant to this section. In addition, Tenant may impose its normal,
customary security procedures in connection with any such inspection and access,
including but not limited to requiring such persons to sign its standard visitor
sign-in sheet.

         20. QUIET ENJOYMENT. If Tenant shall perform all of the covenants and
agreements herein required to be performed by Tenant, Tenant shall, subject to
the terms of this Lease, at all times during the Lease Term, have peaceful and
quiet enjoyment of the Premises against any person claiming by, through or under
Landlord.

         21. SURRENDER. Upon termination of the Lease Term or earlier
termination of Tenant's right of possession, Landlord may, by notice to Tenant,
require Tenant at Tenant's expense to remove the liquid nitrogen tank to be
stored in the truck court outside of the Premises, the microwave
telecommunication equipment, the external utility enclosure for air handling
equipment and compressors and any Trade Fixtures (including air handling
equipment and compressors) and/or any or all Tenant Improvements which Landlord
has not approved, and to repair any damage caused by such removal. Tenant shall
not be required to remove any of the Landlord's Improvements. Any such Trade
Fixtures or Tenant Improvements not so removed by Tenant as permitted or
required herein shall be deemed abandoned and may be stored, removed, and
disposed of by Landlord at Tenant's expense, and Tenant waives all claims
against Landlord for any damages resulting from Landlord's retention and
disposition of such property. All obligations of Tenant hereunder not fully
performed as of the termination of the Lease Term shall survive the termination
of the Lease Term, including without limitation, all payment obligations with
respect to Operating Expenses and all obligations concerning the condition and
repair of the Premises.

         22. HOLDING OVER. If, for any reason, Tenant retains possession of the
Premises after the termination of the Lease Term, unless otherwise agreed in
writing, such possession shall be subject to immediate termination by Landlord
at any time, and all of the other terms and provisions of this Lease (excluding
any expansion or renewal option or other similar right or option) shall be
applicable during such holdover period, except that Tenant shall pay Landlord
from time to time, upon demand, as Base Rent for the holdover period, an amount
equal to 150% the Base Rent in effect on the termination date, computed on a
monthly basis for each month or part thereof during such holding over. All other
payments shall continue under the terms of this Lease. In addition, Tenant shall
be liable for all damages incurred by Landlord as a result of such holding over.
No holding over by Tenant, whether with or without consent of Landlord, shall
operate to extend this Lease except as otherwise expressly provided, and this
Paragraph 22 shall not be construed as consent for Tenant to retain possession
of the Premises.

         23. EVENTS OF DEFAULT. Each of the following events shall be an event
of default ("Event of Default") by Tenant under this Lease:

                  (i) Tenant shall fail to pay any installment of Base Rent or
         any other payment required herein when due, and such failure shall
         continue for a period of 10 days from the date such payment was due (a
         "Monetary Default"). Notwithstanding the foregoing, Tenant shall not be
         in default pursuant to this subsection until Landlord has delivered to
         Tenant the notice required pursuant to Section 4 with respect to the
         late charge.

                  (ii) Tenant or any guarantor or surety of Tenant's obligations
         hereunder shall (A) make a general assignment for the benefit of
         creditors; (B) commence any case, proceeding or other action seeking to
         have an order for relief entered on its behalf as a debtor or to
         adjudicate it a bankrupt or insolvent, or seeking reorganization,
         arrangement, adjustment, liquidation, dissolution or composition of it
         or its debts or seeking appointment of a receiver, trustee, custodian
         or other similar official for it or for all or of any substantial part
         of its property (collectively a "Bankruptcy Proceeding"); (C) become
         the subject of any Bankruptcy Proceeding which is not dismissed within
         60 days of its filing or entry; or (D) die or suffer a legal disability
         (if Tenant, guarantor, or surety is an individual) or be dissolved or
         otherwise fail to maintain its legal existence (if Tenant, guarantor or
         surety is a corporation, partnership or other entity). Notwithstanding
         the foregoing, matters set forth in this Section 23(ii) shall not be an
         Event of Default as long as Tenant continues to fully satisfy all its
         obligations under the Lease.

                  (iii) Any insurance required to be maintained by Tenant
         pursuant to this Lease shall be cancelled or terminated or shall expire
         or shall be reduced or materially changed, except, in each case, as
         permitted in this Lease, and such failure to maintain insurance shall
         continue for more than 10 days after Landlord shall have given Tenant
         written notice of such default.

                  (iv) Tenant shall not occupy or shall vacate the Premises or
         shall fail to continuously operate its business at the Premises for the
         permitted use set forth herein, whether or not Tenant is in monetary or
         other default under this Lease, and such vacating of or failure to
         continuously operate shall continue for more than 30 days after
         Landlord shall have given Tenant written notice of such default.
         Tenant's vacating of or failure to continuously operate the Premises
         shall not constitute an Event of Default if, prior to such action,
         Tenant has made arrangements reasonably acceptable to Landlord to (a)
         insure that Tenant's insurance for the Premises will not be voided or
         cancelled with respect to the Premises as a result of such vacancy, (b)
         insure that the Premises are secured and not subject to vandalism, and
         (c) insure that the Premises will be properly maintained after such
         vacation. Tenant shall inspect the Premises at least once each month
         and report monthly in writing to Landlord on the condition of the
         Premises.

                  (v) Tenant shall attempt or there shall occur any assignment,
         subleasing or other transfer of Tenant's interest in or with respect to
         this Lease except as otherwise permitted in this Lease, and such action
         shall continue for more than 10 days after Landlord shall have given
         Tenant written notice of such default.

                  (vi) Tenant shall fail to discharge or provide a title
         indemnity or a bond for any lien placed upon the Premises in violation
         of this Lease within 30 days after becoming aware that any such lien or
         encumbrance is filed against the Premises.

                  (vii) Tenant shall fail to comply with any provision of this
         Lease other than those specifically referred to in this Paragraph 23,
         and except as otherwise expressly provided therein, such default shall
         continue for more than 30 days after Landlord shall have given Tenant
         written notice of such default.

         24. LANDLORD'S REMEDIES. Upon each occurrence of an Event of Default
and so long as such Event of Default shall be continuing, Landlord may at any
time thereafter at its election: (i) terminate this Lease or Tenant's right of
possession, but Tenant shall remain liable as hereinafter provided; and/or (ii)
pursue any remedies provided for under this Lease or at law or in equity. Upon
the termination of this Lease or termination of Tenant's right of possession, it
shall be lawful for Landlord, without formal demand or notice of any kind, to
re-enter the Premises by summary dispossession proceedings or any other action
or proceeding authorized by law and to remove Tenant and all persons


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and property therefrom. If Landlord re-enters the Premises, Landlord shall have
the right to keep in place and use, or remove and store, all of the furniture,
fixtures and equipment at the Premises.

                  If Landlord terminates this Lease, Landlord may recover from
Tenant the sum of: all Base Rent and all other amounts accrued hereunder to the
date of such termination; the cost of reletting the whole or any part of the
Premises, including without limitation brokerage fees and/or leasing commissions
incurred by Landlord, and costs of removing and storing Tenant's or any other
occupant's property, repairing, altering, remodeling, or otherwise putting the
Premises into condition acceptable to a new tenant or tenants, and all
reasonable expenses incurred by Landlord in pursuing its remedies, including
reasonable attorneys' fees and court costs; and the excess of the then present
value of the Base Rent and other amounts payable by Tenant under this Lease as
would otherwise have been required to be paid by Tenant to Landlord during the
period following the termination of this Lease measured from the date of such
termination to the expiration date stated in this Lease, over the present value
of any net amounts which Tenant establishes Landlord can reasonably expect to
recover by reletting the Premises for such period, taking into consideration the
availability of acceptable tenants and other market conditions affecting
leasing. Such present values shall be calculated at a discount rate equal to the
90-day U.S. Treasury bill rate at the date of such termination.

                  If Landlord terminates Tenant's right of possession (but not
this Lease), Landlord shall use reasonable efforts to relet the Premises for the
account of Tenant for such rent and upon such terms as shall be reasonably
satisfactory to Landlord without thereby releasing Tenant from any liability
hereunder and without demand or notice of any kind to Tenant. If Landlord
terminates Tenant's right to possession without terminating the Lease after an
Event of Default, Landlord shall use commercially reasonable efforts to relet
the Premises; provided, however, (a) Landlord shall not be automatically
obligated to accept any tenant proposed by Tenant, (b) Landlord shall have the
right to lease any other space controlled by Landlord first to the extent it is
commercially reasonable to do so, and (c) any proposed tenant shall meet all of
Landlord's standard leasing criteria then in effect. For the purpose of such
reletting Landlord is authorized to make any repairs, changes, alterations, or
additions in or to the Premises as Landlord deems reasonably necessary or
desirable. If the Premises are not relet, then Tenant shall pay to Landlord as
damages a sum equal to the amount of the rental reserved in this Lease for such
period or periods, plus the cost of recovering possession of the Premises
(including attorneys' fees and costs of suit), the unpaid Base Rent and other
amounts accrued hereunder at the time of repossession, and the costs incurred in
any attempt by Landlord to relet the Premises. If the Premises are relet and a
sufficient sum shall not be realized from such reletting [after first deducting
therefrom, for retention by Landlord, the unpaid Base Rent and other amounts
accrued hereunder at the time of reletting, the cost of recovering possession
(including attorneys' fees and costs of suit), all of the costs and expense of
repairs, changes, alterations, and additions, the expense of such reletting
(including without limitation brokerage fees and leasing commissions) and the
cost of collection of the rent accruing therefrom] to satisfy the rent provided
for in this Lease to be paid, then Tenant shall immediately satisfy and pay any
such deficiency. Any such payments due Landlord shall be made upon demand
therefor from time to time and Tenant agrees that Landlord may file suit to
recover any sums falling due from time to time. Notwithstanding any such
reletting without termination, Landlord may at any time thereafter elect in
writing to terminate this Lease for such previous breach.

                  Exercise by Landlord of any one or more remedies hereunder
granted or otherwise available shall not be deemed to be an acceptance of
surrender of the Premises and/or a termination of this Lease by Landlord,
whether by agreement or by operation of law, it being understood that such
surrender and/or termination can be effected only by the written agreement of
Landlord and Tenant. Any law, usage, or custom to the contrary notwithstanding,
Landlord shall have the right at all times to enforce the provisions of this
Lease in strict accordance with the terms hereof; and the failure of Landlord at
any time to enforce its rights under this Lease strictly in accordance with same
shall not be construed as having created a custom in any way or manner contrary
to the specific terms, provisions, and covenants of this Lease or as having
modified the same. Tenant and Landlord further agree that forbearance or waiver
by Landlord to enforce its rights pursuant to this Lease or at law or in equity,
shall not be a waiver of Landlord's right to enforce one or more of its rights
in connection with any subsequent default. A receipt by Landlord of rent or
other payment with knowledge of the breach of any covenant hereof shall not be
deemed a waiver of such breach, and no waiver by Landlord of any provision of
this Lease shall be deemed to have been made unless expressed in writing and
signed by Landlord. To the greatest extent permitted by law, Tenant waives the
service of notice of Landlord's intention to re-enter as provided for in any
statute, or to institute legal proceedings to that end, and also waives all
right of redemption in case Tenant shall be dispossessed by a judgment or by
warrant of any court or judge. The terms "enter," "re-enter," "entry" or
"re-entry," as used in this Lease, are not restricted to their technical legal
meanings. Any reletting of the Premises shall be on such terms and conditions as
Landlord in its sole discretion may determine (including without limitation a
term different than the remaining Lease Term, rental concessions, alterations
and repair of the Premises, lease of less than the entire Premises to any tenant
and leasing any or all other portions of the Project before reletting the
Premises). Subject to Landlord's agreement to use reasonable efforts to relet
the Premises, Landlord shall not be liable, nor shall Tenant's obligations
hereunder be diminished because of, Landlord's failure to relet the Premises or
collect rent due in respect of such reletting.

         25. TENANT'S REMEDIES/LIMITATION OF LIABILITY. Landlord shall not be in
default hereunder and Tenant shall not have any remedy or cause of action unless
Landlord fails to perform any of its obligations hereunder within 30 days after
written notice from Tenant specifying such failure (unless such performance
will, due to the nature of the obligation, require a period of time in excess of
30 days, then after such period of time as is reasonably necessary). All
obligations of Landlord hereunder shall be construed as covenants, not
conditions; and, except as may be otherwise expressly provided in this Lease,
Tenant may not terminate this Lease for breach of Landlord's obligations
hereunder. Notwithstanding the foregoing, Tenant may terminate this Lease if
Landlord does not diligently pursue the construction of the Building and
Building 4. Lack of diligence will be presumed if the Building is not
Substantially Completed by December 31, 1995, and if Building 4 is not
Substantially Completed by December 31, 1996. All obligations of Landlord under
this Lease will be binding upon Landlord only during the period of its ownership
of the Premises and not thereafter. The term "Landlord" in this Lease shall mean
only the owner, for the time being of the Premises, and in the event of the
transfer by such owner of its interest in the Premises, such owner shall
thereupon be released and discharged from all obligations of Landlord thereafter
accruing, but such obligations shall be binding during the Lease Term upon each
new owner for the duration of such owner's ownership. Any liability of Landlord
under this Lease shall be limited solely to its interest in the Project, and in
no event shall any personal liability be asserted against Landlord in connection
with this Lease nor shall any recourse be had to any other property or assets of
Landlord. This limitation on the liability of Landlord shall only be effective
to the extent that its unencumbered equity in the Project is sufficient to
afford Tenant full recovery on at least $1,000,000.00 in damages; provided,
however, that the foregoing clause shall not be applicable to any mortgagee that
is a purchaser or grantee at a foreclosure or conveyance in lieu of foreclosure
of a mortgage covering the Premises. Except as set forth above, Tenant's
remedies for a breach of Landlord's obligations hereunder will be an action for
damages, specific performance, injunctive or other equitable relief and/or
declaratory judgment. As a further remedy, Tenant will be free to sublet or
assign the Premises subject only to the restriction set forth in Addendum G,
paragraph (a)(ii), (iii), (iv) and (v), (b) and (c). In addition, in the event
of any default by Landlord, Tenant may, after the expiration of all cure periods
and upon 10 days prior written notice to Landlord, take such curative or
self-help actions as it deems reasonably necessary. If Landlord fails to
reimburse Tenant for the reasonable costs, fees and expenses incurred by Tenant
in taking such corrective actions within 30 days after demand therefor,
accompanied by invoices, Tenant may bring an action for damages against Landlord
to recover such costs, fees and expenses together with interest thereon at the
rate provided for in the Lease, and reasonable attorneys' fees incurred by
Tenant in bringing such action for damages.


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         26. SUBORDINATION. Landlord represents and warrants to Tenant that as
of the Commencement Date the Premises will not be pledged, mortgaged or
otherwise encumbered. This Lease and Tenant's interest and rights hereunder are
and shall be subject and subordinate at all times to the lien of any first
mortgage, now existing or hereafter created on or against the Project or the
Premises, and all amendments, restatements, renewals, modifications,
consolidations, refinancing, assignments and extensions thereof, without the
necessity of any further instrument or act on the part of Tenant, provided that
Tenant receives from such mortgagee a commercially reasonable non-disturbance
agreement. In such event, Tenant agrees, at the election of the holder of any
such mortgage, to attorn to any such holder. Tenant agrees upon demand to
execute, acknowledge and deliver such instruments, confirming such subordination
and such instruments of attornment as shall be reasonably requested by any such
holder. Notwithstanding the foregoing, any such holder may at any time
subordinate its mortgage to this Lease, without Tenant's consent, by notice in
writing to Tenant, and thereupon this Lease shall be deemed prior to such
mortgage without regard to their respective dates of execution, delivery or
recording and in that event such holder shall have the same rights with respect
to this Lease as though this Lease had been executed prior to the execution,
delivery and recording of such mortgage and had been assigned to such holder.
The term "mortgage" whenever used in this Lease shall be deemed to include deeds
of trust, security assignments and any other encumbrances, and any reference to
the "holder" of a mortgage shall be deemed to include the beneficiary under a
deed of trust.

         27. MECHANIC'S LIENS. Tenant has no express or implied authority to
create or place any lien or encumbrance of any kind upon, or in any manner to
bind the interest of Landlord or Tenant in, the Premises or to charge the
rentals payable hereunder for any claim in favor of any person dealing with
Tenant, including those who may furnish materials or perform labor for any
construction or repairs. Tenant covenants and agrees that it will pay or cause
to be paid all sums legally due and payable by it on account of any labor
performed or materials furnished in connection with any work performed on the
Premises and that it will save and hold Landlord harmless from all loss, cost or
expense based on or arising out of asserted claims or liens against the
leasehold estate or against the interest of Landlord in the Premises or under
this Lease to the extent such claims or liens arose by, through or under Tenant,
but not otherwise. Tenant shall give Landlord immediate written notice of the
placing of any lien or encumbrance against the Premises and cause such lien or
encumbrance to be discharged within 30 days of the filing or recording thereof;
provided, however, Tenant may contest such liens or encumbrances as long as such
contest prevents foreclosure of the lien or encumbrance and Tenant causes such
lien or encumbrance to be bonded or insured over in a manner satisfactory to
Landlord within such 30 day period.

         28. ESTOPPEL CERTIFICATES. Each party agrees, from time to time, within
10 days after request of the other party, to execute and deliver to the
requesting party, or its designee, any estoppel certificate requested, stating
that this Lease is in full force and effect, the date to which rent has been
paid, that there is no default hereunder (or specifying in detail the nature of
the default), the termination date of this Lease and such other matters
pertaining to this Lease as may be requested. Each party's obligation to furnish
each estoppel certificate in a timely fashion is a material inducement for this
Lease. Accordingly, the cure period for failure to provide an estoppel
certificate shall be limited to ten (10) days.

         29. ENVIRONMENTAL REQUIREMENTS. Tenant shall not permit or cause any
party to bring any Hazardous Material upon the Premises or store or use any
Hazardous Material in or about the Premises without Landlord's prior written
consent, except in de minimus quantities for standard office cleaning and
printing use and except as set forth on Addendum D attached hereto. Tenant, at
its sole cost and expense, shall operate its business in the Premises in
compliance with all Environmental Requirements and shall, in accordance with
Environmental Requirements, immediately remediate any Hazardous Materials
released on or from the Project by Tenant, its agents, employees, contractors,
subtenants or invitees. The term "Environmental Requirements" means all
applicable present and future statutes, regulations, ordinances, rules, codes,
judgments, orders or other similar enactments of any governmental authority or
agency regulating or relating to health, safety, or environmental conditions on,
under, or about the Premises or the environment, including without limitation,
the following: the Comprehensive Environmental Response, Compensation and
Liability Act ("CERCLA"); the Resource Conservation and Recovery Act; and all
state and local counterparts thereto, and any regulations or policies
promulgated or issued thereunder. The term "Hazardous Materials" means and
includes petroleum (as defined in CERCLA) and any substance, material, waste,
pollutant, or contaminant listed or defined as hazardous or toxic, under any
Environmental Requirements.

                  Tenant shall indemnify, defend, and hold Landlord harmless
from and against any and all losses (including, without limitation, diminution
in value of the Premises or the Project and loss of rental income from the
Project), claims, demands, actions, suits, damages (including, without
limitation, punitive damages), expenses (including, without limitation,
remediation, corrective action, or cleanup expenses), and costs (including,
without limitation, actual attorneys' fees, consultant fees or expert fees)
which are brought or recoverable against, or suffered or incurred by Landlord as
a result of any breach of the obligations under this Paragraph 29 by Tenant, its
agents, employees, contractors, subtenants, or invitees, regardless of whether
Tenant had knowledge of such noncompliance. The indemnification and hold
harmless obligations of Tenant shall survive any termination of this Lease.

                  Subject to the requirements of Section 19 hereof, Landlord
shall have reasonable access to, and a right to perform inspections and tests
of, the Premises as it may require to determine Tenant's compliance with
Environmental Requirements and Tenant's obligations under this Paragraph 29.
Access shall be granted to Landlord upon Landlord's prior notice to Tenant and
at such times so as to minimize, so far as may be reasonable under the
circumstances, any disturbance to Tenant's operations. Such inspections and
teats shall be conducted at Landlord's expense, unless such inspections or tests
reveal that Tenant has not complied with any Environmental Requirement, in which
case Tenant shall reimburse Landlord for the reasonable cost of such inspection
and tests. Landlord's receipt of or satisfaction with any environmental
assessment in no way waives any rights that Landlord holds against Tenant.
Landlord will provide Tenant with copies of reports and findings of all
inspections and tests.

                  Landlord agrees to be bound by the environmental covenants,
representations and warranties set forth on Addendum E attached hereto.

         30. RULES AND REGULATIONS. Tenant shall, at all times during the Lease
Term and any extension thereof, comply with all reasonable rules and regulations
at any time or from time to time established by Landlord covering use of the
Premises and the Project. The current rules and regulations are attached hereto
as Exhibit C, and Landlord shall enforce such rules and regulations uniformly
among all Tenants in the Project. In the event of any conflict between said
rules and regulations and other provisions of this Lease, the other terms and
provisions of this Lease shall control. Landlord shall not have any liability or
obligation for the breach of any rules or regulations by other tenants in the
Project, provided that Landlord shall enforce such rules and regulations
consistently throughout the Project.

         31. SECURITY SERVICE. Tenant acknowledges and agrees that, while
Landlord may patrol the Project, Landlord is not providing any security services
with respect to the Premises and that Landlord shall not be liable to Tenant
for, and Tenant waives any claim against Landlord with respect to, any loss by
theft or any other damage suffered or incurred by Tenant in connection with any
unauthorized entry into the Premises or any other breach of security with
respect to the Premises.


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         32. FORCE MAJEURE. Except for the payments of any rent required under
this Lease, which is an independent covenant, Landlord and Tenant shall not be
held responsible for delays in the performance of its obligations hereunder when
caused by strikes, lockouts, labor disputes, acts of God, inability to obtain
labor or materials or reasonable substitutes therefor, governmental
restrictions, governmental regulations, governmental controls, enemy or hostile
governmental action, civil commotion, fire or other casualty, and other causes
beyond the reasonable control of Landlord or Tenant ("Force Majeure").

         33. ENTIRE AGREEMENT. This Lease constitutes the complete agreement of
Landlord and Tenant with respect to the subject matter hereof. No
representations, inducements, promises or agreements, oral or written, have been
made by Landlord or Tenant, or anyone acting on behalf of Landlord or Tenant,
which are not contained herein, and any prior agreements, promises,
negotiations, or representations are superseded by this Lease. This Lease may
not be amended except by an instrument in writing signed by both parties hereto.

         34. SEVERABILITY. If any clause or provision of this Lease is illegal,
invalid or unenforceable under present or future laws, then and in that event,
it is the intention of the parties hereto that the remainder of this Lease shall
not be affected thereby. It is also the intention of the parties to this Lease
that in lieu of each clause or provision of this Lease that is illegal, invalid
or unenforceable, there be added, as a part of this Lease, a clause or provision
as similar in terms to such illegal, invalid or unenforceable clause or
provision as may be possible and be legal, valid and enforceable.

         35. BROKERS. Each party represents and warrants that it has dealt with
no broker, agent or other person in connection with this transaction and that no
broker, agent or other person brought about this transaction, other than the
brokers, if any, set forth on the first page of this Lease, and each party
agrees to indemnify and hold the other harmless from and against any claims by
any other broker, agent or other person claiming a commission or other form of
compensation by virtue of having dealt with the indemnifying party with regard
to this leasing transaction. Landlord agrees to pay all compensation due or to
become due Commercial Industrial Properties and Oxford Commercial in connection
with this transaction.

         36. MISCELLANEOUS.

         (A) Any payments or charges due from Tenant to Landlord hereunder shall
be considered rent for all purposes of this Lease.

         (B) If and when included within the term "Tenant," as used in this
instrument, there is more than one person, firm or corporation, each shall be
jointly and severally liable for the obligations of Tenant.

         (C) All notices required or permitted to be given under this Lease
shall be in writing and shall be sent by registered or certified mail, return
receipt requested, or by a reputable national overnight courier service, postage
prepaid, or by hand delivery addressed to the parties at their addresses below,
with a copy to Landlord at 14100 East 35th Place, Aurora, Colorado 80011. Either
party may by notice given aforesaid change its address for all subsequent
notices. Except where otherwise expressly provided to the contrary, notice shall
be deemed given upon delivery.

         (D) Except as otherwise expressly provided in this Lease or as
otherwise may be required by applicable law, Landlord's granting or withholding
of any consent or approval shall be at its complete discretion.

         (E) At Landlord's request from time to time Tenant shall furnish
Landlord with true and complete copies of the most recent 10-K's and 10-Q's
prepared by Cirrus Logic, Inc.'s accountants to the extent they are intended for
public dissemination.

         (F) Either Landlord or Tenant may prepare and file, and upon request by
the other will execute, a memorandum of lease (which shall not include any
economic or payment terms) in form reasonably satisfactory to the other,
together with a form of release to be issued at the expiration of the Lease.

         (G) The normal rule of construction to the effect that any ambiguities
are to be resolved against the drafting party shall not be employed in the
interpretation of this Lease or any exhibits or amendments hereto.

         (H) The submission by Landlord to Tenant of this Lease shall have no
binding force or effect, shall not constitute an option for the leasing of the
Premises, nor confer any right or impose any obligations upon either party until
execution of this Lease by both parties.

         (I) Words of any gender used in this Lease shall be held and construed
to include any other gender, and words in the singular number shall be held to
include the plural, unless the context otherwise requires. The captions inserted
in this Lease are for convenience only and in no way define, limit or otherwise
describe the scope or intent of this Lease, or any provision hereof, or in any
way affect the interpretation of this Lease.

         (J) Any amount not paid by Tenant within 5 days after its due date in
accordance with the terms of this Lease shall bear interest from such due date
until paid in full at the lesser of the highest rate permitted by applicable law
or 15 percent per year. It is expressly the intent of Landlord and Tenant at all
times to comply with applicable law governing the maximum rate or amount of any
interest payable on or in connection with this Lease. If applicable law is ever
judicially interpreted so as to render usurious any interest called for under
this Lease, or contracted for, charged, taken, reserved, or received with
respect to this Lease, then it is Landlord's and Tenant's express intent that
all excess amounts theretofore collected by Landlord be credited on the
applicable obligation (or, if the obligation has been or would thereby be paid
in full, refunded to Tenant), and the provisions of this Lease immediately shall
be deemed reformed and the amounts thereafter collectible hereunder reduced,
without the necessity of the execution of any new document, so as to comply with
the applicable law, but so as to permit the recovery of the fullest amount
otherwise called for hereunder.

         (K) Construction and interpretation of this Lease shall be governed by
the laws of the state in which the Project is located, excluding any principles
of conflicts of laws.

         (L) Time is of the essence as to the performance of Landlord's and
Tenant's obligations under this Lease.

         (M) All exhibits and addenda attached hereto are hereby incorporated
into this Lease and made a part hereof. In the event of any conflict between
such exhibits or addenda and the terms of this Lease, such exhibits or addenda
shall control.

         (N) The rights and obligations of the parties under this Lease shall be
binding upon and inure to the benefit of the parties hereto and their permitted
successors and assigns.

                                                                         Initial
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                                      -9-
<PAGE>   10


         (O) The Equal Opportunity Clause in Section 202, paragraph 1 through 7
of Executive Order 11246, as amended, and Equal Opportunity Clause
ASPR7-103.18(a) relative to equal employment opportunity and the Implementing
Rules and Regulations of the Office of Federal Contracts Compliance are
incorporated herein by specific reference.

         37. LANDLORD'S LIEN/SECURITY INTEREST. Landlord hereby waives and
releases any security interest or lien that it may have in any of Tenant's
property, either by contract or statute.

         38. LIMITATION OF LIABILITY OF TRUSTEES, SHAREHOLDERS, AND OFFICERS OF
SECURITY CAPITAL INDUSTRIAL TRUST. Any obligation or liability whatsoever of
Security Capital Industrial Trust, a Maryland real estate investment trust,
which may arise at any time under this lease or any obligation or liability
which may be incurred by it pursuant to any other instrument, transaction, or
undertaking contemplated hereby shall not be personally binding upon, nor shall
resort for the enforcement thereof be had to the property of, its trustees,
directors, shareholders, officers, employees or agents, regardless of whether
such obligation or liability is in the nature of contract, tort, or otherwise.

         39. EXPANSION OPTION.

         (A) The following terms shall have the following meanings:

                  (i) The "Option Space" shall mean all or part of Southpark
         Corporate Center 4 ("Building 4"), as shown on Exhibit A hereto.

                  (ii) The "Option Space Commencement Date" shall mean the date
         that is the later of June 30, 1996, or the substantial completion date
         of the Option Space.

         (B) Provided that as of the date Tenant exercises its rights hereunder,
(x) Tenant is the Tenant originally named herein (except for short-term
subtenants related to Tenant's business purpose and affiliates of Tenant), (y)
Tenant actually occupies all of the Premises originally demised under this Lease
and any premises added to the Premises (except for short-term subtenants related
to Tenant's business purpose and affiliates of Tenant, and except for vacancies
permitted pursuant to Subsection 23(iv) hereof), and (z) no Monetary Default or
event which but for the passage of time or the giving of notice, or both, would
constitute a Monetary Default has occurred and is continuing, Tenant shall have
the option to include the portion of the Option Space selected by Tenant as part
of the Premises commencing on the Option Space Commencement Date. In selecting
the Option Space, Tenant shall ensure that the remaining portion of Building 4
not made subject to the option (if any) is of a size and configuration to be
commercially marketable, as reasonably determined by Landlord, and the Option
Space must not be less than 32,000 square feet. If Tenant exercises its right to
include the Option Space as part of the Premises, Tenant shall lease the Option
Space upon all the terms and conditions of the Lease, including the Base Rent
per square foot provided herein (except as set forth in Section 39(F) below)
commencing on the Option Space Commencement Date; provided, however, Tenant
shall not be entitled to any allowances, credits, or abatements with respect
thereto. Notwithstanding the foregoing, Tenant will be entitled to the same
tenant finish allowance per square foot on the Option Space to be paid by
Landlord as with the Building. Landlord will construct and finish out the Option
Space pursuant to the same terms and conditions as set forth on Exhibit B
hereto.

         (C) In addition to its obligation to pay Base Rent (as determined
herein), Tenant shall reimburse and pay Landlord with respect to the Option
Space in the same manner as set forth in the Lease with respect to operating
expenses and other items reimbursable by Tenant. Effective as of the Option
Space Commencement Date, Tenant's Proportionate Share shall be redetermined by
Landlord's architect or construction manager based upon the total floor area of
the Premises (including the Option Space) in proportion to the total floor area
in the Project.

         (D) If Tenant desires to exercise its option for the Option Space,
Tenant must deliver written notice of such exercise to Landlord no later than
January 1, 1996. Time shall be of the essence with respect to the giving of
Tenant's Notice. If Tenant does not exercise its Option by such date, Tenant's
rights under this Section 39 shall be null and void.

         (E) If Landlord is not able to deliver possession of the Option Space
to Tenant by June 30, 1996 because of a Force Majeure event, Landlord shall not
be in default hereunder. In such case, Landlord shall use reasonable efforts to
terminate such Force Majeure event, and the Option Space Commencement Date shall
be the date Landlord is able to deliver possession of the Option Space to
Tenant.

         (F) Notwithstanding Section 39(B) above, if Landlord is subjected to
cost increases in the construction of Building 4 due to:

                  (i) E.E. Reed not agreeing before the commencement of
         construction to honor its existing fixed price contract in the amount
         of $1,215,000 to build Building 4 after reasonable good faith efforts
         by Landlord to require it to do so;

                  (ii) the prime interest rate increasing (as reflected in the
         Wall Street Journal, southwest edition) over the construction period
         interest rate of 8.5% previously used in determining the total shell
         coat of Building 4 between the dates of construction draws on Building
         4 and the date of this Lease (the parties estimate there will be
         approximately $0.095 per square foot per year in additional costs to
         Tenant for each one percent change in the interest rate); or

                  (iii) additional governmental fees and entitlement costs
         (other than those in effect as of the date of this Lease) being
         assessed for the construction of Building 4,

then such additional costs shall be payable by Tenant as an addition to the Base
Rent described above; provided, however, that in the case of (i) and (ii), such
increases shall be passed through to Tenant at a 12% rent constant, and provided
further that if Tenant is not satisfied with any new price suggested by E.E.
Reed, Tenant may require Landlord to rebid the work that is the subject of the
contract and use an alternative bidder reasonably acceptable to Landlord. Tenant
shall be entitled from time to time upon request to receive copies of
documentation from Landlord as may be necessary in Tenant's reasonable judgment
to support and evidence such additional costs. After Tenant delivers its notice
of exercise of its option for the Option Space, Landlord shall notify Tenant in
writing of the total cost increases associated with (i), (ii) and (iii) above.
Upon receipt of Landlord's cost increases, Tenant may for a period of fourteen
(14) days elect by written notice to Landlord to terminate its option for the
Option Space (in which case Tenant shall not owe Landlord any additional sums).



                                                                         Initial
                                                                          JC/RW


                                      -10-


<PAGE>   11
         40. RENEWAL OPTION.

         (A) Provided that as of the time of the giving of the Extension Notice
and the Commencement Date of the Extension Term, (x) Tenant is the Tenant
originally named herein (except for short-term subtenants related to Tenant's
business purpose and affiliates of Tenant), (y) Tenant actually occupies all of
the Premises initially demised under this Lease and any space added to the
Premises (except for short-term subtenants related to Tenant's business purpose
and affiliates of Tenant, and except for vacancies permitted pursuant to
Subsection 23(iv) hereof), and (z) no Monetary Default exists or would exist but
for the passage of time or the giving of notice, or both; then Tenant shall have
the right to extend the Lease Term (at Tenant's election for all or any part of
the original Premises and additional space acquired pursuant to Sections 39, 42
and 43 hereof, provided that the configuration of space to be leased during the
renewal term shall not be in less than 44,000 square foot increments, and shall
not leave any space remaining that is not of a configuration to be commercially
marketable, as reasonably determined by Landlord) for an additional term of 5
years (such additional term is hereinafter called the "Extension Term")
commencing on the day following the expiration of the Lease Term (hereinafter
referred to as the "Commencement Date of the Extension Term"). Tenant shall give
Landlord notice (hereinafter called the "Extension Notice") of its election to
extend the term of the Lease Term at least 6 months prior to the scheduled
expiration date of the Lease Term.

         (B) The Base Rent payable by Tenant to Landlord during the Extension
Term shall be $5.83 per square foot per year.

         (C) The determination of Base Rent does not reduce the Tenant's
obligation to pay or reimburse Landlord for operating expenses and other
reimbursable items as set forth in the Lease, and Tenant shall reimburse and pay
Landlord as set forth in the Lease with respect to such operating expenses and
other items with respect to the Premises during the Extension Term pursuant to
the same cap on such expenses set forth in the Lease, provided that in the first
year of the Renewal Term the cap will be readjusted based on actual expenses for
the first year of the Renewal Term.

         (D) Except for the Base Rent as determined above, Tenant's occupancy of
the Premises during the Extension Term shall be on the same terms and conditions
as are in effect immediately prior to the expiration of the initial Lease Term;
provided, however, Tenant shall have no further right to any allowances, credits
or abatements or any options to contract, renew or extend the Lease, except that
the options afforded Tenant in Sections 42 and 43 will still be in effect during
the Extension Term.

         (E) If Tenant does not give the Extension Notice within the period set
forth in paragraph (A) above, Tenant's right to extend the Lease Term shall
automatically terminate. Time is of the essence as to the giving of the
Extension Notice.

         (F) Landlord shall have no obligation to refurbish or otherwise improve
the Premises for the Extension Term. The Premises shall be tendered on the
Commencement Date of the Extension Term in "as-is" condition.

         (G) If the Lease is extended for the Extension Term, then Landlord
shall prepare and Tenant shall execute an amendment to the Lease confirming the
extension of the Lease Term and the other provisions applicable thereto (the
"Amendment").

         (H) If Tenant exercises its right to extend the term of the Lease for
the Extension Term, the term "Lease Term" as used in the Lease, shall be
construed to include, when practicable, the Extension Term except as provided in
(D) above.

         41. CANCELLATION OPTION.

         Provided no Monetary Default shall then exist and no condition shall
then exist which with the passage of time or giving of notice, or both, would
constitute a Monetary Default, Tenant shall have the right at any time after
four (4) years from the Commencement Date (the "Cancellation Date") to send
Landlord written notice that Tenant has elected to terminate this Lease with
respect to up to 44,000 square feet designated by Tenant effective six months
thereafter.

         Tenant shall have the right, every six months (upon six months prior
written notice to Landlord), to terminate remaining portions of the space
covered by this Lease (provided that each block of space so terminated is not
less than 44,000 square feet and of a configuration so as to be commercially
marketable, as reasonably determined by Landlord) until all the space subject to
this Lease has been terminated from this Lease. In addition, Tenant shall have
the right, at any time after six (6) months after the Cancellation Date to
notify Landlord that it desires to terminate the lease with respect to one-half
of the Premises as designated by Tenant six months thereafter and one-half of
the Premises twelve months thereafter.

         If Tenant elects to terminate this Lease pursuant to the immediately
preceding paragraphs, the effectiveness of such termination (or terminations)
shall be conditioned upon Tenant paying to Landlord an amount equal to the
unamortized portion of $10 per square foot of the space to be terminated,
amortized over the 10 year term of the Lease at an interest rate of 10.5%,
contemporaneously with Tenant's delivery of a Termination Notice to Landlord. In
the event this Cancellation Option is exercised as to the Option Space, the
amortization term will be adjusted to reflect the actual term of the Lease as to
the Option Space. In the event this Cancellation Option is applied to space
acquired pursuant to Sections 42 or 43, the amortization term and tenant finish
numbers will be adjusted to their actual amounts. In addition, as part of the
termination fee, Tenant shall pay to Landlord, contemporaneously with Tenant's
delivery of a Termination Notice to Landlord, the unamortized portion (at a rate
of 10.5% per year for the remaining term of the Lease) of Landlord's costs
incurred in connection with the improvements of the parking lot as set forth on
Exhibit B attached hereto (which shall in no event exceed $50,000.00).

         Notwithstanding anything else herein to the contrary, space acquired
pursuant to the provisions of Sections 39, 42 and 43 hereof cannot be terminated
until three years after it becomes part of the Premises. Landlord will be
entitled to the access rights provided in Section 19 (subject to the conditions
set forth therein) to show the portion of the Premises to be terminated to
prospective tenants upon receipt of a termination notice as to such space.

         42. RIGHT OF FIRST OFFER.

         (A) "Offered Space" shall mean all or any part of the 88,000 square
feet of space in Building 4 described on Exhibit A attached hereto.

         (B) Provided that as of the date of the giving of Landlord's Notice,
(x) Tenant is the Tenant originally named herein (except for short-term
subtenants related to Tenant's business purpose and affiliates of Tenant), (y)
Tenant actually occupies all of the Premises originally demised under this Lease
and any premises added to the Premises (except for short-term subtenants related
to Tenant's business purpose and affiliates of Tenant, and except for vacancies
permitted pursuant to Subsection 23(iv) hereof), and (z) no Monetary Default or
event which but


                                                            Initial
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                                      -11-

<PAGE>   12


for the passage of time or the giving of notice, or both, would constitute a
Monetary Default has occurred and is continuing, if at any time during the term
of this Lease and the Extension Term any lease for any portion of the Offered
Space shall terminate or the space should otherwise become available, Landlord
shall first offer to Tenant the right to include any space that comes available
within the Offered Space as part of the Premises upon all the terms and
conditions of this Lease, except the Base Rent and finish out allowance will be
as then proposed by Landlord to lease the Offered Space, and except that there
will be no caps on increases in Operating Expenses and other reimbursable items
under the Lease.

         (C) Such offer shall be made by Landlord to Tenant in a written notice
(hereinafter called the "Offer Notice") which offer shall designate the space
being offered and shall specify the terms for such Offered Space. Tenant may
accept the offer set forth in the Offer Notice by delivering to Landlord an
unconditional acceptance (hereinafter called "Tenant's Notice") of such offer
within 10 business days after delivery by Landlord of the Offer Notice to
Tenant. Time shall be of the essence with respect to the giving of Tenant's
Notice. If Tenant does not accept (or fails to timely accept) an offer made by
Landlord pursuant to the provisions of this Section with respect to the Offered
Space designated in the Offer Notice, Landlord shall be under no further
obligation with respect to such Offered Space, except that if Landlord desires
to lease the Offered Space pursuant to economic terms that vary in any respect
by ten percent (10%) from that contained in the Offer Notice, Landlord must
first give Tenant the right to lease the Offered Space on the revised terms and
conditions pursuant to the terms of this Section.

         (D) Tenant must accept all Offered Space offered by Landlord at any one
time if it desires to accept any of such Offered Space and may not exercise its
right with respect to only part of such space.

         (E) The rights afforded in this Section shall be in addition to and not
in lieu of the rights afforded Tenant in Section 39 hereof.

         43. ADDITIONAL RIGHT OF FIRST OFFER. Subject only to existing rights of
other current tenants in Southpark Corporate Center, Tenant shall have a right
of first offer during the term of the Lease and the Extension Term, on any space
owned by Landlord in Southpark Corporate Center containing more than 15,000
square feet. All other provisions of Section 42 shall apply to this Additional
Right of First Offer. A schedule showing all existing tenants in Southpark
Corporate Center and their square footage under lease is attached hereto as
Exhibit H.

         IN WITNESS WHEREOF, Landlord and Tenant have executed this Lease as of
the day and year first above written.


TENANT:                                        LANDLORD:

CRYSTAL SEMICONDUCTOR CORPORATION              SECURITY CAPITAL INDUSTRIAL TRUST

By: /s/ JAMES H. CLARDY                        By: /s/ ROBERT J. WATSON
   ------------------------------                 ------------------------------
Name:  James H. Clardy                         Name: Robert J. Watson
Title: President                                    ----------------------------
                                               Title: Managing Director
                                                     ---------------------------


CIRRUS LOGIC, INC.
                                              Address:

By: /s/ JAMES H. CLARDY                       14100 E. 35th Place
   ------------------------------             ---------------------------------
Name:  James H. Clardy                        Aurora, CO 80011
Title: Corporate Officer                      ---------------------------------

                                              ---------------------------------

Address:

4210 S. Industrial Drive
Austin, Texas 78744

                                      -12-
<PAGE>   13




                       THIRD AMENDMENT TO LEASE AGREEMENT


         THIS THIRD AMENDMENT TO LEASE AGREEMENT (this "Third Amendment") is
made and entered into effective as of the 20 day of December, 1996, by and
between SECURITY CAPITAL INDUSTRIAL TRUST ("Landlord"), and CRYSTAL
SEMICONDUCTOR CORPORATION and CIRRUS LOGIC, INC. (together, the "Tenant").

                                   WITNESSETH:

         WHEREAS, Landlord and Tenant have heretofore made and entered into that
certain Lease Agreement, dated as of the 31st day of March, 1995 (the "Original
Lease"), as amended by that certain First Amendment to Lease Agreement dated
August 16, 1995 (the "First Amendment"), that certain Letter Agreement dated
September 29, 1995 ("Letter Agreement"), and that certain Second Amendment to
Lease Agreement dated February 28, 1996 (the "Second Amendment") (subsequent
references to the "Lease" shall mean and refer to the Original Lease, as amended
by the First Amendment, Letter Agreement and Second Amendment), pursuant to
which Tenant currently leases from Landlord Southpark Corporate Center 3,
consisting of 88,000 square feet (the "Existing Premises"), and has agreed to
lease from Landlord Southpark Corporate Center 4, consisting of 88,000 square
feet (the "Option Space"), for a total area of approximately 176,000 square feet
of space (collectively, the "Premises") in a project known as Southpark
Corporate Center (the "Project"), situated in Austin, Texas, said Premises being
depicted on Exhibit A attached to the Lease;

         WHEREAS, Landlord and Tenant desire to establish the Option Space
Commencement Date (as defined in the Second Amendment) as January 1, 1997; and

         WHEREAS, Landlord and Tenant desire to amend the Lease on the terms and
conditions set forth below;

         NOW THEREFORE, for and in consideration of the sum of Ten and No/100
Dollars ($10.00) each to the other in hand paid, the mutual covenants and
agreements of the Lease and this Third Amendment, and other good and valuable
considerations, the receipt and sufficiency of which are hereby acknowledged,
Landlord and Tenant hereby agree as follows:

         1. Except as otherwise specifically provided for herein, all defined
terms used in this Third Amendment shall have the same respective meanings as
are provided for such defined terms in the Lease.

         2. The Option Space Commencement Date is hereby stipulated to be
January 1, 1997. Subparagraph 39(E) of the Original Lease is hereby deleted.
From and after January 1, 1997, (i) all references in the Lease to the
"Premises" shall mean, refer to and include the Existing Premises and the Option
Space, (ii) Tenant's Proportionate Share of Corporate Center 3 shall be 100%,
Tenant's Proportionate Share of Corporate Center 4 shall be 100%, and Tenant's
Proportionate Share of the Project shall be 100%.

         3. The monthly Base Rent for the Option Space shall be as follows:

            Option Space Commencement Date
            (1/1/97) until the last day of the 60th
            full calendar month following the
            Commencement Date of the Lease (9/30/00)            $46,704.45

            First day of the 61st full
            calendar month following the
            Commencement Date of the Lease
            (10/1/00) until the last day of the 120th
            calendar month following the
            Commencement Date of the Lease (9/30/05)            $46,273.33

         4. Landlord shall, at its sole expense, promptly commence and
diligently pursue to completion the construction of the parking lot depicted on
Exhibit B attached hereto (the "Remote Parking Lot"), so as to prevent the
expiration of the existing building permit and site plan for such construction.

         5. (A) Upon written notice from Tenant, Landlord agrees to furnish or
perform at Landlord's sole cost and expense (to the extent of the hereinbelow
referenced Allowance) those items of construction and those improvements
(collectively, the "Corporate Center 4 Tenant Improvements") specified below:

            See Exhibit C attached hereto.

            Landlord has agreed to provide Tenant with a finish-out allowance
of $15.00 per square foot for the Corporate Center 4 Tenant Improvements
($1,320,000.00; the "Allowance"). Landlord will have the cost of the Corporate
Center 4 Tenant Improvements bid by a minimum of three (3) contractors and
present the bids for Tenant's approval. All costs of construction of the
Corporate Center 4 Tenant Improvements in excess of the




<PAGE>   14



Allowance, as reflected by the bid approved by Tenant, shall be borne by Tenant,
and the amount of such costs in excess of the Allowance shall be paid by Tenant
to Landlord prior to commencement of construction. After Tenant's approval of
the bid, Landlord will be responsible for any cost overruns which are not caused
by Tenant changes to the plans and specifications. However, if Tenant shall
desire any further changes from the plans and specifications listed on Exhibit C
hereto (after the approved bid is obtained), Tenant shall so advise Landlord in
writing and Landlord shall reasonably determine whether such changes can be made
in a reasonable and feasible manner. Any and all costs of reviewing any
requested changes, and any and all costs of making any changes to the Corporate
Center 4 Tenant Improvements which Tenant may request and to which Landlord may
agree to shall be at Tenant's sole cost and expense and shall be paid to
Landlord upon demand and before execution of the change order.

            (B) Upon completion of the construction bid process and issuance of
a building permit for the Corporate Center 4 Tenant Improvements, and after
Tenant has paid to Landlord the costs of construction of the improvements in
excess of the Allowance, if any, Landlord shall proceed with and complete the
construction of the Corporate Center 4 Tenant Improvements within 120 days
thereafter, subject to the occurrence of events of Force Majeure (as defined in
the Lease). Landlord shall perform the construction of the Corporate Center 4
Tenant Improvements in a good and workmanlike manner and in conformance with
applicable governmental ordinances, statutes, codes and regulations. As soon as
such improvements have been substantially completed, Landlord shall notify
Tenant in writing of the date that the Corporate Center 4 Improvements were
substantially completed; and if the Corporate Center 4 Tenant Improvements have
not been substantially completed within 120 days following the date on which the
building permit was issued for such improvements (or such later date on which
Tenant has paid to Landlord the amount of the construction costs in excess of
the Allowance), as such date may be extended by Force Majeure, then the Base
Rent payable for the Option Space, as set forth in Paragraph 3 of this Third
Amendment, shall be abated from the date on which such improvements should have
been substantially completed until the date on which the construction of such
Corporate Center 4 Tenant Improvements has been substantially completed. The
Corporate Center 4 Tenant Improvements shall be deemed substantially completed
when, in the reasonable opinion of the construction manager (whether an employee
or agent of Landlord or a third party construction manager) ("Construction
Manager"), (i) such improvements have been completed in good and satisfactory
condition, subject only to completion of punch list items which do not prevent
the utilization of the Option Space for the purposes for which they were
intended in any material way (and which can be completed within 30 days), and
(ii) Landlord has received a satisfactory temporary or final certificate of
occupancy and all necessary permits for the occupation of the Option Space. If
Tenant disputes the Construction Manager's determination of the date of
substantial completion, then the parties agree that the date of substantial
completion shall be the date a temporary or final certificate of occupancy is
issued by the City of Austin.

            (C) Subject to applicable ordinances and building codes governing
Tenant's right to occupy or perform in the Option Space, Tenant shall be allowed
to install its machinery, equipment, fixtures, or other personal property on the
Option Space during the final stages of completion of construction provided that
Tenant does not thereby unreasonably interfere with the completion of
construction or occasion any labor dispute as a result of such installations,
and provided further that Tenant does hereby agree to assume all risk of loss or
damage to such machinery, equipment, fixtures, and other personal property and
to indemnify, defend and hold Landlord harmless from any loss or damage to such
property, and all liability, loss, or damage arising from any injury to the
project or the property of Landlord, its contractors, subcontractors, or
materialmen, and any death or personal injury to any person or persons arising
out of such installations. Delay in putting Tenant in possession of the Option
Space which is the result of a Force Majeure event shall not serve to extend the
term of the Lease or to make Landlord liable for any damages arising therefrom.

            (D) Except for incomplete punch list items and latent defects,
Tenant upon the substantial completion of the Corporate Center 4 Tenant
Improvements shall have and hold the Option Space as the same shall then be
without any liability or obligation on the part of Landlord for making any
further alterations or improvements of any kind in or about the Option Space.

         6. If Tenant, in accordance with any cancellation rights it may have
under Paragraph 41 of the Lease, terminates all or a portion of the space in
Southpark Corporate Center 4 prior to September 30, 2000, then in addition to
any amounts owed by Tenant in accordance with Paragraph 41, for each such
termination of space Tenant shall also pay to Landlord an amount calculated in
accordance with the following formula:

<TABLE>
<CAPTION>
<S>                                                 <C>                              <C>
         Number of days between the date of
         such termination and October 1, 2000   X   Amount of space terminated   X   $4,977.78
         ------------------------------------       --------------------------
                          30                                   88,000
</TABLE>

         The provisions of this Paragraph 6 are intended to supersede in their
entirety (and are not cumulative of) the provisions of Paragraph 8 of the Second
Amendment.

         7. Exhibits A, B and C attached to this Third Amendment are made a part
hereof for all purposes.

         8. Except as modified herein, the Lease and all of the terms and
conditions thereof, shall remain in full force and effect. In the event of any
conflict between the terms and provisions of the Lease and the terms and
provisions of this Third Amendment, the terms and provisions of this Third
Amendment shall supersede and control.


                                       2
<PAGE>   15


This Third Amendment shall be construed under and enforceable in accordance with
the laws of the State of Texas; and shall be binding upon and inure to the
benefit of Landlord and Tenant and their respective successors and permitted
assigns under the Lease (subject to the provisions of Paragraph 17 of the
Lease).

         9. Any obligation or liability whatsoever of Security Capital
Industrial Trust, a Maryland real estate investment trust, which may arise at
any time under the Lease or this Third Amendment, or any obligation or liability
which may be incurred by it pursuant to any other instrument, transaction or
undertaking contemplated hereby, shall not be personally binding upon, nor shall
resort for the enforcement thereof be had to the property of, its trustees,
directors, shareholders, officers, employees, or agents regardless of whether
such obligation or liability is in the nature of contract, tort or otherwise.

         IN WITNESS WHEREOF, the parties hereto have executed this Third
Amendment to be effective as of the day and year first above written.


CRYSTAL SEMICONDUCTOR                      SECURITY CAPITAL INDUSTRIAL TRUST
CORPORATION


By: /s/ CLYDE R. WALLIN                    By: /s/ STEVEN K. MEYER
    ---------------------------------          ---------------------------------
Name: Clyde R. Wallin                      Name: Steven K. Meyer
      -------------------------------            -------------------------------
Title: VP Finance                          Title: Senior Vice President
       ------------------------------             ------------------------------
                                                                      "Landlord"


CIRRUS LOGIC, INC.


By: /s/ JAMES H. CLARDY
    ---------------------------------
Name: James H. Clardy
      -------------------------------
Title: Corporate Officer
       ------------------------------
                             "Tenant"







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