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                                                                   EXHIBIT 10.68


IMPERIAL BANK
INNOVATIVE BUSINESS BANKING
MEMBER FDIC

                                 PROMISSORY NOTE

<TABLE>
<CAPTION>
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    Principal        Loan Date       Maturity      Loan No     Call    Collateral      Account       Officer    Initials
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<S>                 <C>             <C>            <C>         <C>     <C>             <C>           <C>        <C>
  $1,000,000.00     09-11-1998      09-04-2002                                                         257
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         References in the shaded area are for Lender's use only and do not
limit the applicability of this document to any particular loan or item.
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</TABLE>


BORROWER: ALPHA MICROSYSTEMS           LENDER:  IMPERIAL BANK
          2722 S. FAIRVIEW STREET               ORANGE COUNTY REGIONAL OFFICE
          SANTA ANA, CA  92704                  695 TOWN CENTER DRIVE, SUITE 100
                                                COSTA MESA, CA  92626-1924

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<TABLE>
<S>                                <C>                      <C> 
Principal Amount:  $1,000,000.00   Initial Rate:  11.000%   Date of Note:  September 11, 1998
</TABLE>

PROMISE TO PAY. ALPHA MICROSYSTEMS ("Borrower") promises to pay to Imperial Bank
("Lender"), or order, in lawful money of the United States of America, the
principal amount of One Million & 00/100 Dollars ($1,000,0-00.00), together with
interest on the unpaid principal balance from September 11, 1998, until paid in
full.

PAYMENT. Subject to any payment changes resulting from changes in the Index,
Borrower will pay this loan in 47 principal payments of $20,833.00 each and one
final principal and interest payment of $21,046.49. Borrower's first principal
payment is due October 4, 1998, and all subsequent principal payments are due on
the same day of each month after that. In addition, Borrower will pay regular
monthly payments of all accrued unpaid interest due as of each payment date.
Borrower's first interest payment is due October 4, 1998, and all subsequent
interest payments are due on the same day of each month after that. Borrower's
final payment due September 4, 2002, will be for all principal and accrued
interest not yet paid. The annual interest rate for this Note is computed on a
365/360 basis; that is, by applying the ratio of the annual interest rate over a
year of 360 days, multiplied by the outstanding principal balance, multiplied by
the actual number of days the principal balance is outstanding. Borrower will
pay Lender at Lender's address shown above or at such other place as Lender may
designate in writing. Unless otherwise agreed or required by applicable law,
payments will be applied first to any unpaid collection costs and any late
charges, then to any unpaid interest, and any remaining amount to principal.

VARIABLE INTEREST RATE. The interest rate on this Note is subject to change from
time to time based on changes in an index which is the Imperial Bank Prime Rate
(the "Index"). The Prime Rate is the rate announced by Lender as its Prime Rate
of interest from time to time. Lender will tell Borrower the current Index rate
upon Borrower's request. Borrower understands that Lender may make loans based
on other rates as well. The interest rate change will not occur more often than
each day. The Index currently is 8.500%. The interest rate to be applied to the
unpaid principal balance of this Note will be at a rate of 2.500 percentage
points over the Index, resulting in an initial rate of 11.000%. NOTICE: Under no
circumstances will the interest rate on this Note be more than the maximum rate
allowed by applicable law.

PREPAYMENT; MINIMUM INTEREST CHARGE. In any event, even upon full prepayment of
this Note, Borrower understands that Lender is entitled to a minimum interest
charge of $250.00. Other than Borrower's obligation to pay any minimum interest
charge, Borrower may pay without penalty all or a portion of the amount owed
earlier than it is due. Early payments will not, unless agreed to by Lender in
writing, relieve Borrower of Borrower's obligation to continue to make payments
under the payment schedule. Rather, they will reduce the principal balance due
and may result in Borrower making fewer payments.

LATE CHARGE. If a payment is 10 days or more late, Borrower will be charged
5.000% of the unpaid portion of the regularly scheduled payment.

DEFAULT. Borrower will be in default if any of the following happens: (a)
Borrower fails to make any payment when due. (b) Borrower breaks any promise
Borrower has made to Lender, or Borrower fails to comply with or to perform when
due any other term, obligation, covenant, or condition contained in this Note or
any agreement related to this note, or in any other agreement or loan Borrower
has with Lender. (c) Any representation or statement made or furnished to Lender
by Borrower or on Borrower's behalf is false or misleading in any material
respect either now or at the time made or furnished. (d) Borrower becomes
insolvent, a receiver is appointed for any part of Borrower's property, Borrower
makes an assignment for the benefit of creditors, or any proceeding is commenced
either by Borrower or against Borrower under any bankruptcy or insolvency laws.
(e) Any creditor tries to take any of Borrower's property on or in which Lender
has a lien or security interest. This includes a garnishment of any of
Borrower's accounts with Lender. (f) Any guarantor dies or any of the other
events described in this 
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default section occurs with respect to any guarantor of this Note. (g) A
material adverse change occurs in Borrower's financial condition, or Lender
believes the prospect of payment or performance of the indebtedness is impaired.
(h) Lender in good faith deems itself insecure.

If any default, other than a default in payment, is curable and if Borrower has
not been given a notice of a breach of the same provision of this note within
the preceding twelve (12) months, it may be cured (and no event or default will
have occurred) if Borrower, after receiving written notice from Lender demanding
cure of such default: (a) cures the default within ten (10) days; or (b) if the
cure requires more than ten (10) days, immediately initiates steps which Lender
deems in Lender's sole discretion to be sufficient to cure the default and
thereafter continues and completes all reasonable and necessary steps sufficient
to produce compliance as soon as reasonably practical.

LENDER'S RIGHTS. Upon default, Lender may declare the entire unpaid principal
balance on this Note and all accrued unpaid interest immediately due, without
notice, and then Borrower will pay that amount. Upon Borrower's failure to pay
all amounts declared due pursuant to this section, including failure to pay upon
final maturity, Lender, at its option, may also, if permitted under applicable
law, do one or both of the following: (a) increase the variable interest rate on
this note to 7.500 percentage points over the Index, and (b) add any unpaid
accrued interest to principal and such sum will bear interest therefrom until
paid at the rate provided in this note (including any increased rate). Lender
may hire or pay someone else to help collect his Note if Borrower does not pay.
Borrower also will pay Lender that amount. This includes, subject to any limits
under applicable law, Lender's attorney's fees and Lender's legal expenses
whether or not there is a lawsuit, including attorneys' fees and legal expenses
for bankruptcy proceedings (including efforts to modify or vacate any automatic
stay or injunction), appeals, and any anticipated post-judgment collection
services. Borrower also will pay any court costs, in addition to all other sums
provided by law. This Note has been delivered to Lender and accepted by Lender
in the State of California. If there is a lawsuit, Borrower agrees that Lender's
request to submit to the jurisdiction of the courts of Los Angeles County, the
State of California. Lender and Borrower hereby waive the right to any jury
trial in any action, proceeding, or counterclaim brought by either Lender or
Borrower against the other. (Initial Here /s/ JJD) This Note shall be governed
by and construed in accordance with the laws of the State of California.

DISHONORED ITEM FEE. Borrower will pay a fee to Lender of $25.00 if Borrower
makes a payment on Borrower's loan and the check or preauthorized charge with
which Borrower pays is later dishonored.

RIGHT OF SETOFF. Borrower grants to Lender a contractual security interest in,
and hereby assigns, conveys, delivers, pledges, and transfers to Lender all
Borrower's right, title and interest in and to, Borrower's accounts with Lender
(whether checking, savings, or some other account), including without limitation
all accounts held jointly with someone else and all accounts Borrower may open
in the future, excluding however all IRA and Keogh accounts, and all trust
accounts for which the grant of a security interest would be prohibited by law.
Borrower authorizes Lender, to the extent permitted by applicable law, to charge
or setoff all sums owing on this Note against any and all such accounts.

REFERENCE PROVISION. 1. Other than (i) non-judicial foreclosure and all matters
in connection therewith regarding security interests in real or personal
property; or (ii) the appointment of a receiver, or the exercise of other
provisional remedies (any and all of which may be initiated pursuant to
applicable law), each controversy, dispute or claim between the parties arising
out of or relating to this document ("Agreement"), which controversy, dispute or
claim is not settled in writing within thirty (30) days after the "Claim Date"
(defined as the date on which a party subject to the Agreement gives written
notice to all other parties that a controversy, dispute or claim exists), will
be settled by a reference proceeding in California in accordance with the
provisions of Section 638 et seq. of the California Code of Civil Procedure, or
their successor section ("CCP"), which shall constitute the exclusive remedy for
the settlement of any controversy, dispute or claim concerning this Agreement,
including whether such controversy, dispute or claim is subject to the reference
proceeding and except as set forth above, the parties waive their rights to
initiate any legal proceedings against each other in any court of jurisdiction
other than the Superior Court in the County where the Real Property, if any, is
located or Los Angeles County if none (the "Court"). The referee shall be a
retired Judge of the Court selected by mutual agreement of the parties, and if
they cannot so agree within forty-five (45) days after the Claim Date, the
referee shall be promptly selected by the Presiding Judge of the Court (or his
representative). The referee shall be appointed to sit as a temporary judge,
with all of the powers for a temporary judge, as authorized by law, and upon
selection should take and subscribe to the oath of office as provided for in
Rule 244 of the California Rules of Court (or any subsequently enacted Rule).
Each party shall have one peremptory challenge pursuant to CCP 170.6. The
referee shall (a) be requested to set the matter for hearing within sixty (60)
days after the Claim Date and (b) try any and all issues of law or fact and
report a statement of decision upon them, if possible, within ninety (90) days
of the Claim Date. Any decision rendered by the referee will be final, binding
and conclusive and judgment shall be entered pursuant to CCP 644 in any court in
the State of California having jurisdiction. Any party may apply for a reference
proceeding at an time after thirty (30) days following notice to any other party
of the nature of the controversy, dispute or claim, by filing a petition for a
hearing and/or trial. All discovery permitted by this Agreement shall be
completed no later than fifteen (15) days before the first hearing date
established by the referee. The referee may extend such period in the event of a
party's refusal to provide requested discovery for any reason whatsoever,
including, without limitation, legal objections raised to such discovery or
unavailability of a witness due to absence or illness. No party shall be
entitled to "priority" in conducting discovery. Depositions may be taken by
either party upon seven (7) days written notice, and request for 
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production or inspection of documents shall be responded to within ten (10) days
after service. All disputes relating to discovery which cannot be resolved by
the parties shall be submitted to the referee whose decision shall be final and
binding upon the parties. Pending appointment of the referee as provided herein,
the Superior Court is empowered to issue temporary and/or provisional remedies,
as appropriate.

2. Except as expressly set forth in this Agreement, the referee shall determine
the manner in which the reference proceeding is conducted including the time and
place of all hearings, the order of presentation of evidence, and all other
questions that arise with respect to the course of the reference proceeding. All
proceedings and hearings conducted before the referee, except for trial, shall
be conducted without a court reporter, except that when any party so requests, a
court reporter will be used at any hearing conducted before the referee. The
party making such a request shall have the obligation to arrange for and pay for
the court reporter. The costs of the court reporter at the trial shall be borne
equally by the parties.

3. The referee shall be required to determine all issues in accordance with
existing case law and the statutory laws of the State of California. The rules
of evidence applicable to proceedings at law in the State of California will be
applicable to the reference proceeding. The referee shall be empowered to enter
equitable as well as legal relief, to provide all temporary and/or provisional
remedies and to enter equitable orders that will be binding upon the parties.
The referee shall issue a single judgment at the close of the reference
proceeding which shall dispose of all of the claims of the parties that are the
subject of the reference. The parties hereto expressly reserve the right to
contest or appeal from the final judgment or any appealable order of appealable
judgment entered by the referee. The parties hereto expressly reserve the right
to findings of fact, conclusions of law, a written statement of decision, and
the right to move for a new trial or a different judgment, which new trial, if
granted, is also to be a reference proceeding under this provision.

4. In the event that the enabling legislation which provides for appointment of
a referee is repealed (and no successor statute is enacted), any dispute between
the parties that would otherwise be determined by the reference procedure herein
described will be resolve and determined by arbitration. The arbitration will be
conducted by a retired judge of the Court, in accordance with California
Arbitration Act, 1280 through 1294.2 of the CCP as amended from time to time.
The limitations with respect to discovery as set forth hereinabove shall apply
to any such arbitration proceeding.

CREDIT AGREEMENT. This Note is subject to the provisions of the Credit Terms and
Conditions Agreement dated June 9, 1998 and all amendments thereto and
replacements therefor.

GENERAL PROVISIONS. Lender may delay or forgo enforcing any of its rights or
remedies under this Note without losing them. Borrower and any other person who
signs, guarantees or endorses this Note, to the extent allowed by law, waive any
applicable statute of limitations, presentment, demand for payment, protest and
notice of dishonor. Upon any change in the terms of this Note, and unless
otherwise expressly stated in writing, no party who signs this Note, whether as
maker, guarantor, accommodation maker or endorser, shall be released from
liability. All such parties agree that Lender may renew or extend (repeatedly
and for any length of time) this loan, or release any party or guarantor or
collateral; or impair, fail to realize upon or perfect Lender's security
interest in the collateral; and take any other action deemed necessary by Lender
without the consent of or notice to anyone. All such parties also agree that
Lender may modify this loan without the consent of or notice to anyone other
than the party with whom the modification is made.

PRIOR TO SIGNING THIS NOTE, BORROWER READ AND UNDERSTOOD ALL THE PROVISIONS OF
THIS NOTE, INCLUDING THE VARIABLE INTEREST RATE PROVISIONS. BORROWER AGREES TO
THE TERMS OF THE NOTE AND ACKNOWLEDGES RECEIPT OF A COMPLETED COPY OF THE NOTE.

BORROWER:

ALPHA MICROSYSTEMS

By: /s/ Jeffrey J. Dunnigan
    ------------------------------------------------
    JEFFREY J. DUNNIGAN, VICE PRESIDENT/FINANCE/CFO

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