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                                                                     EXHIBIT 4.1

                          REGISTRATION RIGHTS AGREEMENT

        THIS REGISTRATION RIGHTS AGREEMENT (the "Agreement") is made and entered
into as of October 20, 2000, between LSI Logic Corporation, a Delaware
corporation ("Parent"), and Roger A. Franklin (the "Holder's Agent"), as agent
for the shareholders listed on Schedule A hereto (the "Shareholders").

                                    RECITALS

        A. Pursuant to an Agreement and Plan of Reorganization dated as of
October 20, 2000 by and among Parent, Sapphire Acquisition Corporation, a
Washington corporation and wholly-owned subsidiary of Parent (the "Merger Sub"),
Syntax Systems, Inc., a Washington corporation (the "Company"), the Holder's
Agent and certain other parties thereto (the "Merger Agreement"), the parties
thereto have agreed, subject to the terms and conditions set forth therein, to
merge Merger Sub with and into the Company (the "Merger") and thereby to convert
all shares of capital stock of the Company then outstanding into Parent Common
Stock (as such term is defined in the Merger Agreement) upon the terms and
subject to the conditions described in the Merger Agreement.

        B. The Shareholders desire to have liquidity with respect to the shares
of Parent Common Stock they receive in the Merger.

        C. Parent desires to grant each of the Shareholders registration rights
as provided herein.

        NOW, THEREFORE, in consideration of the promises and the mutual
covenants and agreements herein contained, the Company and the Holder's Agent,
on behalf of the Shareholders, agree as follows:

        1. Definitions of Certain Terms. As used herein, the following terms
shall have the following meanings. Capitalized terms used but not otherwise
defined in this Agreement shall have the meanings given to them in the Merger
Agreement.

               (a) "Closing Date" means the Closing Date as defined in Article I
of the Merger Agreement.

               (b) "Exchange Act" means the Securities Exchange Act of 1934, as
amended, and the rules and regulations of the SEC issued thereunder, as they may
be in effect from time to time.

               (c) "Form S-3" means such form under the Securities Act as in
effect on the date hereof or any registration form under the Securities Act
subsequently adopted by the SEC which similarly permits inclusion or
incorporation of substantial information by reference to other documents filed
by the Company with the commission.

               (d) "Holder" means any Shareholder holding Registrable Shares and
any other person or entity holding Registrable Shares to whom the registration
rights granted in this Agreement have been transferred pursuant to Section 8
hereof.

               (e) "Registrable Shares" means the shares of Parent Common Stock
issued to the Shareholders pursuant to the Merger (including shares held in the
escrow account), and any other securities issued by Parent as a dividend or
other distribution with respect to, or in exchange for or in replacement of,
such shares; provided, however, Registrable Shares shall not include shares of
Parent Common Stock that

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have been registered under the Securities Act and disposed of pursuant to the
registration statement used to effect such registration or that can be sold
without registration in accordance with Rule 144 of the Securities Act.

               (f) "SEC" means the United States Securities and Exchange
Commission, or any governmental agency succeeding to its functions.

               (g) "Securities Act" means the Securities Act of 1933, as
amended, and the rules and regulations of the SEC issued thereunder, as they may
be in effect from time to time.

        2. Shelf Registration. Parent agrees that as soon as possible, but not
later than fifteen (15) days of the Closing Date, Parent shall cause to be filed
a registration statement (a "Shelf Registration") on Form S-3 under the
Securities Act for an offering to be made on a delayed or continuous basis
pursuant to Rule 415 thereunder or any similar rule that may be adopted by the
SEC and permitting sales in ordinary course brokerage or dealer transactions not
involving any underwritten public offering, covering all of the Registrable
Shares. Parent shall use commercially reasonable efforts thereafter (a) to cause
the Shelf Registration to be declared effective by the SEC as promptly as
practicable and (b) subject to Sections 3 and 4 hereof, to keep the Shelf
Registration continuously effective until the earlier to occur of (i) subject to
any extension of time pursuant to Section 4(b) of this Agreement, the first
anniversary of the Closing Date (the "Time Period"), and (ii) the first date on
which no Registrable Shares originally covered by the Shelf Registration shall
constitute Registrable Shares (such period during which the Shelf Registration
is effective is referred to herein as the "Registration Period").

     3. Registration Procedures. After Parent commences the registration of the
Registrable Shares pursuant to the Shelf Registration, Parent shall take all
reasonable actions to permit registration and sale of the Registrable Shares
pursuant to the Shelf Registration, including the following:

               (a) furnish to the Holders such number of copies of the Shelf
Registration, each amendment and supplement thereto (in each case including all
exhibits thereto), the prospectus included in the Shelf Registration (including
any preliminary prospectus) and such other documents as the Holders may
reasonably request in order to facilitate the disposition of the Registrable
Shares owned by the Holders;

               (b) use commercially reasonable efforts to register or qualify
such Registrable Shares under such other securities or "blue sky" laws of such
jurisdictions as the Holder's Agent reasonably requests in writing and to do any
and all other acts and things that may be reasonably necessary or advisable to
register or qualify for sale in such jurisdictions the Registrable Shares owned
by the Holders; provided, however, that Parent shall not be required (i) to
qualify to do business in any jurisdiction where it is not then so qualified or
(ii) to consent to general service of process in any jurisdiction where it is
not then so subject to service of process; and

               (c) use commercially reasonable efforts as promptly as
practicable to cause all Registrable Shares covered by the Shelf Registration to
be listed on the New York Stock Exchange or other securities exchange or market,
if any, on which similar securities issued by Parent are then listed.

     4. Stop Order; Postponement of Registration.

               (a) Parent will notify the Holders promptly of (i) the issuance
of any stop order suspending the effectiveness of the Shelf Registration or (ii)
the receipt by Parent of any notification with respect to the suspension of the
qualification of the Registrable Shares for sale in any jurisdiction.
Immediately upon receipt of any such notice, the Holders shall cease to offer
and sell any Registrable Shares


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pursuant to the Shelf Registration in the jurisdiction to which such stop order
or suspension relates. Parent shall use all reasonable efforts to prevent the
issuance of any such stop order or the suspension of any such qualification and,
if any such stop order is issued or any such qualification is suspended, to
obtain as soon as possible the withdrawal or revocation thereof, and will notify
the Holders at the earliest practicable date of the date on which the Holders
may offer and sell Registrable Shares pursuant to the Shelf Registration.

               (b) Parent will notify the Holders promptly of the occurrence of
any event or the existence of any state of facts that, in the reasonable
judgment of Parent, should be or could be required to be set forth in the
prospectus used in connection with the Shelf Registration (the "Prospectus");
provided, however, that Parent shall not be required to disclose such event or
facts, or the nature thereof, to the Holders. Immediately upon receipt of such
notice, the Holders shall cease to offer or sell any Registrable Shares pursuant
to such Prospectus, cease to deliver or use such Prospectus and, if so requested
by Parent, return to Parent, at its expense, all copies (other than permanent
file copies) of such Prospectus. Promptly after Parent determines that the
information may be included in an amendment or supplement to the Prospectus,
Parent will use commercially reasonable efforts to amend or supplement such
Prospectus as promptly as practicable in order to set forth or reflect such
event or state of facts. In the event that Parent determines in good faith that
the disclosure of such information would be detrimental to Parent or its
shareholders, Parent shall be permitted to delay the filing of such an amendment
or supplement to the Prospectus for a period of time to extend no longer than
sixty (60) days. Parent shall not exercise this delay right more than three
times in any twelve month period. Parent will furnish copies of such amendment
or supplement to the Prospectus to the Holders. In the event Holders are
prevented from selling Registrable Shares through the Shelf Registration as a
result of this Section 4(b), then the Time Period shall be extended by the
number of days that such Holders are prevented from making such sales as a
result of this Section 4(b).

        5. Information Concerning the Holders.

               (a) The obligations of Parent to take the actions contemplated by
Sections 2 and 3 hereof with respect to an offering of Registrable Shares shall
be subject to the condition that each Holder shall (i) conform to all applicable
requirements of the Securities Act and the Exchange Act with respect to the
offering and sale of securities and (ii) advise each underwriter, broker or
dealer through which any of such Registrable Shares are offered that such
Registrable Shares are part of a distribution that is subject to the prospectus
delivery requirements of the Securities Act. Each Holder shall furnish to Parent
in writing such information and furnish such documents as may be reasonably
required by Parent in the preparation of (A) the Prospectus (or any amendment or
supplement thereto) with respect to any offering of Registrable Shares and (B)
any qualification of such Registrable Shares under state securities or "blue
sky" laws pursuant to Section 3(b) hereof, and shall promptly notify Parent of
the occurrence, from the date on which such information or documents are
furnished to the date of the closing for the sale of such Registrable Shares, of
any event relating to such Holder that is required under the Securities Act to
be set forth in the Prospectus (or any amendment or supplement thereto).

               (b) At the end of the Registration Period, the Holders shall
discontinue sales of Registrable Shares pursuant to the Shelf Registration after
Parent has given notice to the Holders of its intention to remove from
registration the securities covered by the Registration Statement which remain
unsold, and the Holders shall notify Parent promptly upon receipt of such notice
from Parent of the number of shares of the Holders that are registered but
remain unsold.

        6. Expenses of Registration. Parent shall pay all reasonable expenses
incident to its performance of or compliance with this Agreement and
registration of Registrable Shares in connection herewith, including (a) all
SEC, stock exchange or market and National Association of Securities Dealers,


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Inc. registration and filing fees, (b) all fees and expenses incurred in
complying with securities or "blue sky" laws, (c) all printing, messenger and
delivery expenses, (d) all fees and disbursements of Parent's independent public
accountants and counsel, and (e) the reasonable fees and expenses of counsel to
the Holders, not to exceed a total of $25,000 (all of such expenses herein
referred to as "Registration Expenses"). The Registration Expenses shall not
include any sales or underwriting discounts, commissions or fees attributable to
the sale of the Registrable Shares, which shall be borne by the Holders.

        7. Indemnification and Contribution.

               (a) Parent agrees to indemnify, to the extent permitted by law
and subject to the terms of this Agreement, each Holder and its directors,
officers, employees and agents and each person, if any, who controls such Holder
(within the meaning of the Securities Act) against any losses, claims, damages,
liabilities and expenses (including reasonable attorneys' fees) arising out of
or based upon any untrue or alleged untrue statement of a material fact
contained in the Shelf Registration (or any amendment thereto) or the Prospectus
(or any amendment or supplement thereto) or any omission or alleged omission to
state therein a material fact required to be stated therein or necessary to make
the statements made therein in the light of the circumstances under which they
were made not misleading; provided, however, that Parent shall not be liable to
any Holder or its directors, officers, employees or agents or each person, if
any, who controls such Holder (within the meaning of the Securities Act) (i) to
the extent that any such loss, claim, damage, liability or expense arises out
of, or is based upon any untrue or alleged untrue statement, or any omission, if
such statement or omission shall have been made in reliance upon and in
conformity with information relating to such Holder or person furnished in
writing to Parent by such Holder or person expressly for use in the preparation
of the Shelf Registration (or any amendment thereto) or the Prospectus (or any
amendment or supplement thereto) or (ii) if a copy of the Prospectus (or any
amendment thereto) relating to the Shelf Registration was not sent or given by
or on behalf of such Holder to a purchaser of the Holder's Registrable Shares,
if required by law so to have been delivered, at or prior to the written
confirmation of the sale of the Registrable Shares to such purchaser, and if the
Prospectus (as so amended or supplemented) would have cured the defect giving
rise to such loss, claim, damage or liability.

               (b) In connection with the Shelf Registration, each Holder will
indemnify, to the extent permitted by law and subject to the terms of this
Agreement, Parent, its directors, officers, employees and agents and each person
who controls Parent (within the meaning of the Securities Act) against any
losses, claims, damages, liabilities and expenses (including reasonable
attorneys' fees) arising out of or based upon any untrue or alleged untrue
statement of a material fact contained in the Shelf Registration (or any
amendment thereto) or the Prospectus (or any amendment or supplement thereto) or
any omission or alleged omission to state therein a material fact required to be
stated therein or necessary to make the statements made therein in the light of
the circumstances under which they were made not misleading, to the extent that
such untrue statement or omission was made in reliance upon and in conformity
with information furnished in writing to Parent by such Holder expressly for use
in the preparation of the Shelf Registration (or any amendment thereto) or the
Prospectus (or any amendment or supplement thereto); provided, that the
liability of each Holder hereunder shall be limited to the proportion of any
such loss, claim, damage, liability or expense which is equal to the proportion
that the public offering price of the shares by such Holder under such
registration statement bears to the total public offering price of all
securities sold thereunder, but not in any event to exceed the net proceeds
received by such Holder.

               (c) Each party entitled to indemnification under this Section 7
(the "Indemnified Party") shall give notice to the party required to provide
indemnification (the "Indemnifying Party") promptly after such Indemnified Party
has actual knowledge of any claim as to which indemnity may be sought, and shall
permit the Indemnifying Party to assume the defense of any such claim or any
litigation resulting therefrom; provided that counsel for the Indemnifying
Party, who shall conduct the defense of such claim or litigation,


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shall be approved by the Indemnified Party (whose approval shall not be
unreasonably withheld or delayed); and provided, further, that the delay or
failure of any Indemnified Party to give notice as provided herein shall not
relieve the Indemnifying Party of its obligations under this Section 7, except
to the extent that the Indemnifying Party shall have been materially adversely
affected by such delay or failure. The Indemnified Party may participate in such
defense at the Indemnified Party's expense; provided, however, that the
Indemnifying Party shall pay any such reasonable expense if the Indemnified
Party shall have reasonably concluded that there may be a conflict between the
positions of the Indemnifying Party and the Indemnified Party in conducting the
defense of any such claim or litigation resulting therefrom. No Indemnified
Party shall consent to entry of any judgment or settle any claim or litigation
without the prior written consent of the Indemnifying Party.

               (d) If the indemnification provided for in this Section 7 from
the Indemnifying Party is unavailable to an Indemnified Party hereunder in
respect of any losses, claims, damages, liabilities or expenses referred to
therein as a result of a judicial determination that such indemnification may
not be enforced in such case notwithstanding this Agreement, the Indemnifying
Party, in lieu of indemnifying such Indemnified Party, shall contribute to the
amount paid or payable by such Indemnified Party as a result of such losses,
claims, damages, liabilities or expenses in such proportion as is appropriate to
reflect the relative fault of the Indemnifying Party and Indemnified Party in
connection with the actions which resulted in such losses, claims, damages,
liabilities or expense, as well as any other relevant equitable considerations.
The relative fault of such Indemnifying Party and Indemnified Party shall be
determined by reference to, among other things, whether any action in question,
including any untrue or alleged untrue statement of material fact or omission or
alleged omission to state a material fact, has been made by, or relates to
information supplied by, such Indemnifying Party or Indemnified Party, and the
parties' relative intent, knowledge, access to information and opportunity to
correct or prevent such action; provided, however, that no person guilty of
fraudulent misrepresentation (within the meaning of Section 11(f) of the
Securities Act) shall be entitled to contribution from any person who was not
guilty of such fraudulent misrepresentation and no Holder will be required to
contribute any amount in excess of the public offering price (less underwriting
discounts and selling commissions) of all such Registrable Stock offered by it
pursuant to such Registration Statement.

        8. Transfer of Registration Rights. The registration rights of any
Holder (and of any transferee of any Holder or its transferees) under this
Agreement with respect to any Registrable Shares may be transferred to any
transferee who (i) acquires at least 50,000 (or, if less, all of the Registrable
Shares of a Holder) of such Registrable Shares, (ii) is a partner, member or
stockholder of a Holder that is a partnership, limited liability company or
corporation, respectively, or (iii) is a family member of a Holder or a trust or
family limited partnership controlled by a Holder; provided that Parent is given
written notice by the Holder at the time of such transfer stating the name and
address of the transferee and identifying the Registrable Shares with respect to
which the rights under this Agreement are being assigned and such transferee
executes and delivers such agreements as Parent may reasonably require in order
to confirm that such transferee agrees to be bound by this Agreement.

        9. Amendment of Registration Rights. This Agreement may not be amended,
modified or supplemented by the parties hereto in any manner, except by a
written instrument that is approved by the Holder's Agent and Insight Venture
Partners I, L.P. ("Insight") and is signed by Parent and the Holder's Agent.

        10. Termination. The registration rights set forth in this Agreement
shall terminate as to any Holder at the earlier of such time as (i) subject to
any extension of time pursuant to Section 4(b) of this Agreement, the first
anniversary of the Closing Date, or (ii) the first date on which no Registrable
Shares originally covered by the Shelf Registration shall constitute Registrable
Shares.

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        11. Grant of Additional Registration Rights. The Holders acknowledge
that Parent may acquire other companies and in the course of such acquisitions
may grant the equity owners thereof registration rights with respect to their
shares of Parent on terms that would be negotiated at such time and may be
materially different than the terms of this Agreement.

        12. No Waiver. The terms and conditions of this Agreement may be waived
only by a written instrument (a) approved by the Holder's Agent and Insight and
signed by the Holder's Agent in the case where a Holder or the Holder's Agent is
waiving compliance and (b) signed by Parent in the case where Parent is waiving
compliance. The failure of any party hereto to enforce at any time any of the
provisions of this Agreement shall in no way be construed to be a waiver of any
such provision, nor in any way to affect the validity of this Agreement or any
part hereof or the right of such party thereafter to enforce each and every such
provision. No waiver of any breach of or non-compliance with this Agreement
shall be held to be a waiver of any other or subsequent breach or
non-compliance. The rights and remedies herein provided are cumulative and are
not exclusive of any rights or remedies that any party may otherwise have at law
or in equity.

        13. Governing Law. This Agreement shall be governed by and construed and
enforced in accordance with the laws of the State of California, regardless of
the other laws that might govern under applicable principles of conflicts of
laws thereof.

        14. Notice. All notices and other communications hereunder shall be in
writing and shall be deemed given if delivered by hand, sent by facsimile
transmission with confirmation of receipt, sent via a reputable overnight
courier service with confirmation of receipt requested, or mailed by registered
or certified mail (postage prepaid and return receipt requested) to the parties
at the following addresses (or at such other address for a party as shall be
specified by like notice), and shall be deemed given on the date on which
delivered by hand or otherwise on the date of receipt as confirmed:

        To Parent:

        LSI Logic Corporation
        1551 McCarthy Boulevard
        Milpitas, California 95035
        Attn:  Vice President and General Counsel
        Telephone No.:(408) 433-7189
        Facsimile No.:(408) 433-6896

        with a copy to:

        Wilson Sonsini Goodrich & Rosati, P.C.
        650 Page Mill Road
        Palo Alto, California 94304
        Attn:  Kathleen B. Bloch, Esq.
        Telephone No.:(650) 493-9300
        Facsimile No.:(650) 493-6811

        To the Holder's Agent:

        Roger A. Franklin
        33650 Sixth Avenue South
        Federal Way, Washington  98003


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        Telephone No.: (253) 838-2626
        Facsimile No.:  (253) 815-1882

        with a copy to:

        Dennis Seinfeld, Esq.
        920 Fawcett Avenue
        Tacoma, Washington 98401
        Telephone No.:  (253) 620-1500
        Facsimile No.:   (253) 572-3052

        To a Holder:

        At their respective addresses appearing on Parent's stock register.

        15. Construction of Agreement. A reference to a Section or Schedule
shall mean a Section in or Schedule to this Agreement unless otherwise expressly
stated. The titles and headings herein are for reference purposes only and shall
not in any manner limit the construction of this Agreement which shall be
considered as a whole. The words "include," "includes" and "including" when used
herein shall be deemed in each case to be followed by the words "without
limitation."

        16. Entire Agreement, Assignability, etc. This Agreement and the Merger
Agreement and the documents and other agreements among the parties hereto and
thereto as contemplated by or referred to herein or therein constitute the
entire agreement among the parties with respect to the subject matter hereof and
supersede all other prior agreements and understandings, both written and oral,
between the parties with respect to the subject matter hereof. This Agreement
shall be binding upon and inure to the benefit of the parties hereto and their
respective successors and permitted assigns. This Agreement is not intended to
confer upon any person other than the parties hereto and the Shareholders any
rights or remedies hereunder, except as otherwise expressly provided herein and
shall not be assignable by operation of law or otherwise, except as provided in
Section 8 hereof.

        17. Validity. The invalidity or unenforceability of any provision of
this Agreement shall not affect the validity or enforceability of any other
provision of this Agreement, each of which shall remain in full force and
effect.

        18. Counterparts. This Agreement may be executed in one or more
counterparts, all of which together shall constitute one and the same Agreement.



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        IN WITNESS WHEREOF, the parties have caused this Registration Rights
Agreement to be executed as an agreement under seal as of the date first written
above.


                                       LSI LOGIC CORPORATION



                                       By:    /s/  Thomas Georgens
                                          ------------------------------------
                                              Name:  Thomas Georgens
                                              Title:  Vice President



                                       HOLDER'S AGENT



                                       By:    /s/  Roger A. Franklin
                                          ------------------------------------
                                              Roger A. Franklin






                [SIGNATURE PAGE TO REGISTRATION RIGHTS AGREEMENT]





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                                   Schedule A

                                  Shareholders