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                                                                     EXHIBIT 4.2


                         REGISTRATION RIGHTS AGREEMENT

                 This Registration Rights Agreement is made and entered into as
of September 12, 1996, by and among S3 Incorporated, a Delaware corporation
(the "Company"), and Lehman Brothers Inc., PaineWebber Incorporated and Cowen &
Company (the "Initial Purchasers") who have purchased or have the right to
purchase up to $103,500,000 in aggregate principal amount of 5-3/4% Convertible
Subordinated Notes due 2003 (the "Notes") of the Company pursuant to the
Purchase Agreement (as such term is defined below).

                 This Agreement is made pursuant to the Purchase Agreement,
dated September 12, 1996, among the Company and the Initial Purchasers (the
"Purchase Agreement").  In order to induce the Initial Purchasers to enter into
the Purchase Agreement, the Company has agreed to provide the registration
rights provided for in this Agreement to the Initial Purchasers and their
respective direct and indirect transferees (i) for the benefit of the Initial
Purchasers, (ii) for the benefit of the holders from time to time of the Notes
(including the Initial Purchasers) and the holders from time to time of the
Common Stock issuable or issued upon conversion of the Notes and (iii) for the
benefit of the securities constituting the Transfer Restricted Securities.  The
execution of this Agreement is a condition to the closing of the transactions
contemplated by the Purchase Agreement.

                 The parties hereby agree as follow:

                 1.       Definitions.  As used in this Agreement, the
following terms shall have the following meanings:

                 Advice:  As defined in Section 2(d) hereof.

                 Affiliate:   An affiliate of any specified person shall mean
any other person directly or indirectly controlling or controlled by or under
direct or indirect common control with such specified person.  For the purposes
of this definition, "control," when used with respect to any person, means the
power to direct the management and policies of such person, directly or
indirectly, whether through the ownership of voting securities, by contract or
otherwise and the terms "affiliated," "controlling" and "controlled" have
meanings correlative to the foregoing.

                 Agreement:  This Registration Rights Agreement, as the same
may be amended, supplemented or modified from time to time in accordance with
the terms hereof.




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                 Business Day:  Each Monday, Tuesday, Wednesday, Thursday and
Friday that is not a day on which banking institutions in New York, New York
are authorized or obligated by law or executive order to close.

                 Closing Date:  September 18, 1996.

                 Common Stock:  Common Stock, $.0001 par value per share, of
the Company and any other shares of common stock as may constitute "Common
Stock" for purposes of the Indenture, in each case, as issuable or issued upon
conversion of the Notes.

                 Company:  S3 Incorporated, a Delaware corporation, and any
successor corporation thereto.

                 controlling person:  As defined in Section 5(a) hereof.

                 Effectiveness Period:  As defined in Section 2(a) hereof.

                 Effectiveness Target Date:  The 180th day following the
Closing Date.

                 Exchange Act:  The Securities Exchange Act of 1934, as
amended, and the rules and regulations promulgated by the SEC pursuant thereto.

                 Filing Date:  The 90th day after the Closing Date.

                 Holder:  Each owner of any Transfer Restricted Securities.

                 Indemnified Person:  As defined in Section 5(a) hereof.

                 Indenture:  The Indenture, dated as of the date hereof,
between the Company and the Trustee thereunder, pursuant to which the Notes are
being issued, as amended, modified or supplemented from time to time in
accordance with the terms thereof.

                 Initial Purchasers:  As defined in the first paragraph hereof.

                 Notes:  The $90,000,000 aggregate principal amount of 5-3/4%
Convertible Subordinated Notes due 2003 of the Company being issued pursuant to
the Indenture (together with the up to $13,500,000 aggregate principal amount
of such Notes, if, and to the extent the Initial Purchasers' over allotment
option is exercised).

                 Proceeding:  An action, claim, suit or proceeding (including,
without limitation, an investigation or partial proceeding, such as
disposition), whether commenced or threatened.

                 Prospectus:  The prospectus included in any Registration
Statement (including, without limitation, a prospectus that discloses
information previously omitted from a prospectus filed as part of an effective
registration statement in reliance upon Rule





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430A promulgated pursuant to the Securities Act), as amended or supplemented by
any prospectus supplement, with respect to the resale of any of the Transfer
Restricted Securities covered by such Registration Statement, and all other
amendments and supplements to any such prospectus, including post-effective
amendments, and all materials incorporated by reference or deemed to be
incorporated by reference, if any, in such prospectus.

                 Purchase Agreement:  As defined in the second paragraph
hereof.

                 Registration Statement:  Any registration statement of the
Company filed with the SEC pursuant to the Securities Act that covers the
resale of any of the Transfer Restricted Securities pursuant to the provisions
of this Agreement, including the Prospectus, amendments and supplements to such
registration statement or Prospectus, including pre- and post-effective
amendments, all exhibits thereto, and all material incorporated by reference or
deemed to be incorporated by reference, if any, in such registration statement.

                 Rule 144:  Rule 144 promulgated by the SEC pursuant to the
Securities Act, as such Rule may be amended from time to time, or any successor
rule or regulation.

                 Rule 144A:  Rule 144A promulgated by the SEC pursuant to the
Securities Act, as such Rule may be amended from time to time, or any successor
rule or regulation.

                 Rule 158:  Rule 158 promulgated by the SEC pursuant to the
Securities Act, as such Rule may be amended from time to time, or any successor
rule or regulation.

                 Rule 174:  Rule 174 promulgated by the SEC pursuant to the
Securities Act, as such Rule may be amended from time to time, or any successor
rule or regulation.

                 Rule 415:  Rule 415 promulgated by the SEC pursuant to the
Securities Act, as such Rule may be amended from time to time, or any successor
rule or regulation.

                 Rule 424:  Rule 424 promulgated by the SEC pursuant to the
Securities Act, as such Rule may be amended from time to time, or any successor
rule or regulation.

                 SEC:  The Securities and Exchange Commission.

                 Securities Act:  The Securities Act of 1933, as amended, and
the rules and regulations promulgated by the SEC thereunder.

                 Shelf Registration Statement:  As defined in Section 2(a)
hereof.

                 Special Counsel:  Any special counsel to the holders of
Transfer Restricted Securities.

                 TIA:  The Trust Indenture Act of 1939, as amended.





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                 Transfer Restricted Securities:  The Notes and the shares of
Common Stock into which the Notes are converted or convertible (including any
shares of Common Stock issued or issuable thereon upon any stock split, stock
combinations, stock dividend or the like), upon original issuance thereof, and
at all times subsequent thereto, and associated related rights, if any, until,
in the case of any such Note or share (and associated rights) (i) the date on
which the resale thereof has been registered effectively pursuant to the
Securities Act and disposed of in accordance with the Registration Statement
relating thereto, (ii) the date on which either such Note or the shares of
Common Stock issued upon conversion of such Note are distributed to the public
pursuant to Rule 144 (or any similar provisions then in effect) or are saleable
pursuant to Rule 144(k) promulgated by the SEC pursuant to the Securities Act
or (iii) the date on which it ceases to be outstanding, whichever date is
earliest.

                 Trustee:  The Trustee under the Indenture.

                 Underwritten registration or underwritten offering:  A
registration in connection with which securities of the Company are sold to an
underwriter for reoffering to the public pursuant to an effective Registration
Statement.

                 References herein to the term "Holders of a majority in
aggregate principal amount of Transfer Restricted Securities" or words to a
similar effect shall mean, with respect to any request, notice, demand,
objection or other action by the holders of Transfer Restricted Securities
hereunder or pursuant hereto (each, an "Act"), registered holders of a number
of shares of then outstanding Common Stock constituting Transfer Restricted
Securities and an aggregate principal amount of then outstanding Notes
constituting Transfer Restricted Securities, such that the sum of such shares
of Common Stock and the shares of Common Stock issuable upon conversion of such
Notes constitute in excess of 50% of the sum of all of the then outstanding
shares of Common Stock constituting Transfer Restricted Securities and the
number of shares of Common Stock issuable upon conversion of then outstanding
Notes constituting Transfer Restricted Securities. For purposes of the
immediately preceding sentence, (i) any Holder may elect to take any Act with
respect to all or any portion of Transfer Restricted Securities held by it and
only the portion as to which such Act is taken shall be included in the
numerator of the fraction described in the preceding sentence and (ii) Transfer
Restricted Securities owned, directly or indirectly, by the Company or its
Affiliates shall be deemed not to be outstanding.

                 2.       Shelf Registration Statement.  (a)  The Company
agrees to file with the SEC as soon as practicable after the Closing Date, but
in no event later than the Filing Date, a Registration Statement for an
offering to be made on a continuous basis pursuant to Rule 415 covering all of
the Transfer Restricted Securities (the "Shelf Registration Statement").  The
Shelf Registration Statement shall be on Form S-3 under the Securities Act or
another appropriate form selected by the Company permitting registration of
such Transfer Restricted Securities for resale by the Holders in the manner or
manners reasonably designated by them (including, without limitation, one or
more underwritten offerings).  The Company shall not permit any securities
other than the Transfer Restricted Securities to be included in the Shelf
Registration Statement.  The Company shall use all reasonable efforts





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to cause the Shelf Registration Statement to be declared effective pursuant to
the Securities Act as promptly as practicable following the filing thereof, but
in no event later than the Effectiveness Target Date, and to keep the Shelf
Registration Statement continuously effective under the Securities Act for 36
months after the date on which all the Notes are sold (including those sold
pursuant to the over-allotment option granted to the Initial Purchasers in the
Purchase Agreement) to the Initial Purchasers (subject to extension pursuant to
Sections 2(a), 2(b) and 2(d) hereof) (the "Effectiveness Period"), or such
shorter period ending when there cease to be outstanding any Transfer
Restricted Securities; provided that the Company shall not be deemed to have
kept a Registration Statement effective during the applicable period if it
voluntarily takes or fails to take any action that results in selling Holders
of the Transfer Restricted Securities covered thereby not being able to sell
such Transfer Restricted Securities pursuant to Federal securities laws during
that period (and the time period during which such Registration Statement is
required to remain effective hereunder shall be extended by the number of days
during which such selling Holders of Transfer Restricted Securities are not
able to sell Transfer Restricted Securities).

                 (b)      Supplements and Amendments.  The Company shall use
its reasonable efforts to keep the Shelf Registration Statement continuously
effective by supplementing and amending the Shelf Registration Statement if
required by the rules, regulations or instructions applicable to the
registration form used for such Shelf Registration Statement, if required by
the Securities Act, or if reasonably requested by the Holders of a majority in
aggregate principal amount of the Transfer Restricted Securities or by any
underwriter of such Transfer Restricted Securities; provided that the
Effectiveness Period shall be extended to the extent required to permit dealers
to comply with the applicable prospectus delivery requirements of Rule 174 and
as otherwise provided herein.

                 (c)      Selling Securityholder Information.  The Company may
require each Holder of Transfer Restricted Securities to be sold pursuant to
the Shelf Registration Statement to furnish to the Company such information
regarding the Holder and the distribution of the Transfer Restricted Securities
as the Company may from time to time reasonably require for inclusion in the
Shelf Registration Statement, and the Company may exclude from such
registration the Transfer Restricted Securities of any Holder that unreasonably
fails to furnish such information within a reasonable time after receiving such
request.  Each Holder of Transfer Restricted Securities to be sold pursuant to
a Shelf Registration Statement agrees to furnish to the Company all information
required to be disclosed in order to make the information previously furnished
to the Company by such Holder not misleading.

                 (d)      Certain Notices; Suspension of Sales.  Each Holder of
Transfer Restricted Securities agrees by acquisition of such Transfer
Restricted Securities that, upon receipt of any notice from the Company of the
happening of any event of the kind described in Section 3(c)(ii), 3 (c)(iii),
3(c)(v) or 3(c)(vi) hereof, such Holder will forthwith discontinue disposition
of such Transfer Restricted Securities covered by such Registration Statement
or Prospectus (other than in transactions exempt from the registration
requirements under the Securities Act) until such Holder's receipt of the
copies of the





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supplemented or amended Prospectus contemplated by Section 3(j) hereof, or
until it is advised in writing (the "Advice") by the Company that the use of
the applicable Prospectus may be resumed, and, in either case, has received
copies of any additional or supplemental filings that are incorporated or
deemed to be incorporated by reference in such Prospectus.  If the Company
shall give any such notice, the Effectiveness Period shall be extended by the
number of days during such period from and including the date of the giving of
such notice to and including the date when each Holder shall have received (x)
the copies of the supplemented or amended Prospectus contemplated by Section
3(j) hereof or (y) the Advice, and, in either case, has received copies of any
additional or supplemental filings that are incorporated or deemed to be
incorporated by reference in such Prospectus.

                 (e)      Compliance.  The Company shall cause the Shelf
Registration Statement and the Prospectus and any amendment or supplement
thereto, as of the effective date of the Shelf Registration Statement,
amendment or supplement, (i) to comply in all material respects with the
applicable requirements of the Securities Act and the rules and regulations of
the SEC and (ii) not to contain any untrue statement of a material fact or omit
to state a material fact required to be stated therein or necessary in order to
make the statements therein, in the light of the circumstances under which they
were made, not misleading.

                 3.       Registration Procedures.  In connection with the
Company's registration obligations hereunder, the Company shall effect such
registrations on the appropriate form selected by the Company available for the
sale of the Transfer Restricted Securities to permit the sale of Transfer
Restricted Securities in accordance with the intended method or methods of
disposition thereof, and pursuant thereto the Company shall as expeditiously as
possible:

                 (a)      No fewer than five Business Days prior to the initial
filing of a Registration Statement or Prospectus and no fewer than two Business
Days prior to the filing of any amendment or supplement thereto (including any
document that would be incorporated or deemed to be incorporated therein by
reference), furnish to the registered (as of the most recent reasonably
practicable date which shall not be more than two Business Days prior to the
date such notice is personally delivered, delivered to a next-day courier,
deposited in the mail or telecopied, as the case may be) Holders of the
Transfer Restricted Securities, Special Counsel and the managing underwriters,
if any, copies of all such documents proposed to be filed, which documents
(including those incorporated or deemed to be incorporated by reference) will
be subject to the review of such Holders, Special Counsel and such
underwriters, if any, and cause the officers and directors of the Company,
counsel to the Company and independent certified public accountants to the
Company to respond to such inquiries as shall be necessary in connection with
such Registration Statement, in the opinion of respective counsel to such
Holders and such underwriters, to conduct a reasonable investigation within the
meaning of the Securities Act.  The Company shall not file any such
Registration Statement or related Prospectus or any amendments or supplements
thereto to which the Holders of a majority in aggregate principal amount of the
Transfer Restricted Securities, Special Counsel, or the managing underwriters,
if any, shall reasonably object on a timely basis;





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                 (b)      Prepare and file with the SEC such amendments,
including post-effective amendments, to each Registration Statement as may be
necessary to keep such Registration Statement continuously effective for the
applicable time period set forth in Section 2(a) hereof; and cause the related
Prospectus to be supplemented by any required Prospectus supplement, and as so
supplemented to be filed pursuant to Rule 424 (or any similar provisions then
in force) under the Securities Act and the Exchange Act with respect to the
disposition of all securities covered by such Registration Statement during
such period in accordance with the intended methods of disposition by the
sellers thereof set forth in such Registration Statement as so amended or in
such Prospectus as so supplemented;

                 (c)      Notify the registered (as of the most recent
reasonably practicable date which shall not be more than two Business Days
prior to the date such notice is personally delivered, delivered to a next-day
courier, deposited in the mail or telecopied, as the case may be) Holders of
Transfer Restricted Securities to be sold or Special Counsel and the managing
underwriters, if any, promptly (and in the case of an event specified by clause
(i)(A) of this paragraph in no event fewer than two Business Days prior to such
filing), and (if requested by any such person), confirm such notice in writing,
(i)(A) when a Prospectus or any Prospectus supplement or post-effective
amendment is proposed to be filed, and, (B) with respect to a Registration
Statement or any post-effective amendment, when the same has become effective,
(ii) of any request of the SEC or any other Federal or state governmental
authority for amendments or supplements to a Registration Statement or related
Prospectus or for additional information related thereto, (iii) of the issuance
by the SEC, any state securities commission, any other governmental agency or
any court of any stop order, order or injunction suspending or enjoining the
use or the effectiveness of a Registration Statement or the initiation of any
proceedings for that purpose, (iv) if at any time any of the representations
and warranties of the Company contained in any agreement (including any
underwriting agreement) contemplated by Section 3(l) hereof are not true and
correct in all material respects, (v) of the receipt by the Company of any
notification with respect to the suspension of the qualification or exemption
from qualification of any of the Transfer Restricted Securities for sale in any
jurisdiction, or the initiation or threatening of any proceeding for such
purpose, and (vi) of the existence of any fact and the happening of any event
that makes any statement made in such Registration Statement or related
Prospectus untrue in any material respect, or that requires the making of any
changes in such Registration Statement or Prospectus so that in the case of the
Registration Statement, it will not contain any untrue statement of a material
fact or omit to state any material fact required to be stated therein or
necessary to make the statements therein not misleading and that, in the case
of the Prospectus, such Prospectus will not contain any untrue statement of a
material fact or omit to state any material fact required to be stated therein
or necessary to make the statements therein, in the light of the circumstances
under which they were made, not misleading;

                 (d)      Use all reasonable efforts to avoid the issuance of,
or, if issued, obtain the withdrawal of any order enjoining or suspending the
use or effectiveness of a Registration Statement or the lifting of any
suspension of the qualification (or exemption from qualification) of any of the
Transfer Restricted Securities for sale in any jurisdiction, at the earliest
practicable moment;





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                 (e)      Subject to Section 2(c) hereof, if reasonably
requested by the managing underwriters, if any, or the Holders of a majority in
aggregate principal amount of the Transfer Restricted Securities being sold in
connection with such offering, (i) promptly incorporate in a Prospectus
supplement or post-effective amendment such information as the managing
underwriters, if any, and such Holders agree should be included therein, and
(ii) make all required filings of such Prospectus supplement or such
post-effective amendment as soon as practicable after the Company has received
notification of the matters to be incorporated in such Prospectus supplement or
post-effective amendment; provided, however, that the Company shall not be
required to take any action pursuant to this Section 3(e) that would, in the
opinion of counsel for the Company, violate applicable law;

                 (f)      Furnish to each Holder who so requests, Special
Counsel and each managing underwriter, if any, without charge, at least one
conformed copy of each Registration Statement and each amendment thereto,
including financial statements (but excluding schedules, all documents
incorporated or deemed to be incorporated therein by reference and all
exhibits, unless requested in writing by such Holder, counsel or managing
underwriter);

                 (g)      Deliver to each Holder, Special Counsel, and the
underwriters, if any, without charge, as many copies of the Prospectus or
Prospectuses (including each form of prospectus) and each amendment or
supplement thereto to such persons who reasonably request; and, unless the
Company shall have given notice to such Holder pursuant to Section 3(c)(vi),
the Company hereby consents to the use of such Prospectus and each amendment or
supplement thereto by each of the selling Holders of Transfer Restricted
Securities and the underwriters, if any, in connection with the offering and
sale of the Transfer Restricted Securities covered by such Prospectus and any
amendment or supplement thereto;

                 (h)      Prior to any public offering of Transfer Restricted
Securities, use all reasonable efforts to register or qualify, or cooperate
with the Holders of Transfer Restricted Securities to be sold, the
underwriters, if any, and their respective counsel in connection with the
registration or qualification (or exemption from such registration or
qualification) of, such Transfer Restricted Securities for offer and sale under
the securities or Blue Sky laws of such jurisdictions within the United States
as any Holder or underwriter reasonably requests in writing, keep each such
registration or qualification (or exemption therefrom) effective during the
period such Registration Statement is required to be kept effective and do any
and all other acts or things necessary legally to enable the disposition in
such jurisdictions of the Transfer Restricted Securities covered by the
applicable Registration Statement; provided, however that the Company shall not
be required to qualify generally to do business in any jurisdiction where it is
not then so qualified or take any action that would subject it to general
service of process in any such jurisdiction where it is not then so subject;

                 (i)      In connection with any sale or transfer of Transfer
Restricted Securities that will result in such securities no longer being
Transfer Restricted Securities, and unless any Transfer Restricted Securities
shall be in only book-entry form, cooperate





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with the Holders and the managing underwriters, if any, to (A) facilitate the
timely preparation and delivery of certificates representing Transfer
Restricted Securities to be sold, which certificates shall not bear any
restrictive legends, shall bear a CUSIP number different from the CUSIP number
for the Transfer Restricted Securities and shall be in a form eligible for
deposit with The Depository Trust Company and (B) enable such Transfer
Restricted Securities to be in such denominations and registered in such names
as the managing underwriters, if any, or Holders may request at least two
Business Days prior to any sale of Transfer Restricted Securities;

                 (j)      Upon the occurrence of any event contemplated by
Section 3(c)(vi) hereof, as promptly as practicable, prepare a supplement or
amendment, including, if appropriate, a post-effective amendment, to each
Registration Statement or a supplement to the related Prospectus or any
document incorporated or deemed to be incorporated therein by reference, and
file any other required document so that, as thereafter delivered, such
Prospectus will not contain an untrue statement of a material fact or omit to
state a material fact required to be stated therein or necessary to make the
statements therein, in the light of the circumstances under which they were
made, not misleading;

                 (k)      Prior to the effective date of the first Registration
Statement relating to the Transfer Restricted Securities, to provide a CUSIP
number for the Transfer Restricted Securities to be sold pursuant to the
Registration Statement;

                 (l)      Enter into such agreements (including an underwriting
agreement in form, scope and substance as is customary in underwritten
offerings) reasonably satisfactory to the Company and take all such other
reasonable actions in connection therewith (including those reasonably
requested by the managing underwriters, if any, or the Holders of a majority in
aggregate principal amount of the Transfer Restricted Securities being sold) in
order to expedite or facilitate the disposition of such Transfer Restricted
Securities, and in such connection, whether or not an underwriting agreement is
entered into and whether or not the registration is an underwritten
registration, (i) make such representations and warranties to the Holders of
such Transfer Restricted Securities and the underwriters, if any, with respect
to the business of the Company and its subsidiaries (including with respect to
businesses or assets acquired or to be acquired by any of them), and the
Registration Statement, Prospectus and documents, if any, incorporated or
deemed to be incorporated by reference therein, in each case, in form,
substance and scope as are customarily made by issuers to underwriters in
underwritten offerings and reasonably acceptable to the Company, and confirm
the same if and when requested; (ii) seek to obtain opinions of counsel to the
Company and updates thereof (which counsel and opinions (in form, scope and
substance) shall be reasonably satisfactory to the managing underwriters, if
any, and Special Counsel to the Holders of the Transfer Restricted Securities
being sold, addressed to each selling Holder of Transfer Restricted Securities
and each of the underwriters, if any, covering the matters customarily covered
in opinions requested in underwritten offerings (including any such matters as
may be reasonably requested by such Special Counsel and underwriters); (iii)
use all reasonable efforts to obtain customary "cold comfort" letters and
updates thereof from the independent certified public accountants of the
Company (and, if necessary, any other independent certified public accountants
of any subsidiary of the Company or of any





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business acquired or to be acquired by the Company for which financial
statements and financial data is, or is required to be, included in the
Registration Statement), addressed (where reasonably possible) to each selling
Holder of Transfer Restricted Securities and each of the underwriters, if any,
such letters to be in customary form and covering matters of the type
customarily covered in "cold comfort" letters in connection with underwritten
offerings; (iv) if an underwriting agreement is entered into, the same shall
contain indemnification provisions and procedures no less favorable to the
selling Holders of Transfer Restricted Securities and the underwriters, if any,
than those set forth in Section 5 hereof (or such other provisions and
procedures acceptable to Holders of a majority in aggregate principal amount of
the Transfer Restricted Securities covered by such Registration Statement and
the managing underwriters); and (v) deliver such documents and certificates as
may be reasonably requested by the Holders of a majority in aggregate principal
amount of the Transfer Restricted Securities being sold, Special Counsel or the
managing underwriters, if any, to evidence the continued validity of the
representations and warranties made pursuant to clause (i) of this Section 3(l)
and to evidence compliance with any customary conditions contained in the
underwriting agreement or other agreement entered into by the Company;

                 (m)      Make available for inspection by a representative of
the Holders of Transfer Restricted Securities being sold, any underwriter
participating in any such disposition of Transfer Restricted Securities, if
any, and any attorney, consultant or accountant retained by such selling
Holders or underwriter, at the offices where normally kept, during reasonable
business hours, all financial and other records, pertinent corporate documents
and properties of the Company and its subsidiaries as they may reasonably
request (including with respect to business and assets acquired or to be
acquired to the extent that such information is available to the Company), and
cause the officers, directors, agents and employees of the Company and its
subsidiaries (including with respect to business assets acquired or to be
acquired to the extent that such information is available to the Company) to
supply all information in each case reasonably requested by any such
representative, underwriter, attorney, consultant or accountant in connection
with such Registration Statement; provided, however, that any information that
is reasonably and in good faith designated by the Company in writing as
confidential at the time of delivery of such information shall be kept
confidential by such persons (and such persons shall so agree in writing),
unless (i) disclosure of such information is required by court or
administrative order or is necessary to respond to inquiries of regulatory
authorities, (ii) disclosure of such information is required by law (including
any disclosure requirements pursuant to Federal securities laws in connection
with the filing of any Registration Statement or the use of any prospectus
referred to in this Agreement), (iii) such information becomes generally
available to the public other than as a result of a disclosure or failure to
safeguard by any such person or (iv) such information becomes available to any
such person from a source other than the Company and such source is not bound
by a confidentiality agreement;

                 (n)      Cause the Indenture to be qualified under the TIA not
later than the effective date of the first Registration Statement relating to
the Transfer Restricted Securities; and in connection therewith, cooperate with
the Trustee under the Indenture and the Holders of the Transfer Restricted
Securities to effect such changes to the Indenture, if any, as may be required
for such Indenture to be so qualified in accordance with the terms





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of the TIA; and execute, and use all reasonable efforts to cause the Trustee to
execute, all customary documents as may be required to effect such changes, and
all other forms and documents (including the Form T-1) required to be filed
with the SEC to enable the Indenture to be so qualified under the TIA in a
timely manner;

                 (o)      Comply with applicable rules and regulations of the
SEC and make generally available to its security holders earning statements
satisfying the provisions of Section 11(a) of the Securities Act and Rule 158
thereunder (or any similar rule promulgated under the Securities Act), no later
than 45 days after the end of any 12-month period (or 90 days after the end of
any 12-month period if such period is a fiscal year), commencing on the first
day of the first fiscal quarter after the effective date of a Registration
Statement, which statement shall cover said period, consistent with the
requirements of Rule 158; and

                 (p)      (i) list all Common Stock covered by such
Registration Statement on any securities exchange on which the Common Stock is
then listed or (ii) authorize for quotation on The Nasdaq Stock Market all
Common Stock covered by such Registration Statement if the Common Stock is then
so authorized for quotation.

                 4.       Registration Expenses.

                 (a)      All fees and expenses incident to the performance of
or compliance with this Agreement by the Company shall be borne by it whether
or not any Registration Statement is filed or becomes effective and whether or
not any securities are issued or sold pursuant to any Registration Statement.
The fees and expenses referred to in the foregoing sentence shall include,
without limitation, (i) all registration and filings fees (including without
limitation, fees and expenses (A) with respect to filings required to be made
with the National Association of Securities Dealers, Inc. and (B) in compliance
with securities or Blue Sky laws (including, without limitation and in addition
to that provided for in (b) below, fees and disbursements of counsel for the
underwriters or Special Counsel for the Holders in connection with Blue Sky
qualifications of the Transfer Restricted Securities and determination of the
eligibility of the Transfer Restricted Securities for investment under the laws
of such jurisdictions as the managing underwriters, if any, or Holders of a
majority in aggregate principal amount of Transfer Restricted Securities, may
designate)), (ii) printing expenses (including, without limitation, expenses of
printing certificates for Transfer Restricted Securities in a form eligible for
deposit with The Depository Trust Company and of printing Prospectuses if the
printing of Prospectuses is required by the managing underwriters, if any, or
by the Holders of a majority in aggregate principal amount of the Transfer
Restricted Securities included in any Registration Statement), (iii) messenger,
telephone and delivery expenses, (iv) fees and disbursements of counsel for the
Company and Special Counsel for the Holders (plus any local counsel, deemed
appropriate by the Holders of a majority in aggregate principal amount of the
Transfer Restricted Securities) in accordance with the provisions of Section
4(b) hereof, (v) fees and disbursements of all independent certified public
accountants referred to in Section 3(l)(iii) (including, without limitation,
the expenses of any special audit and "cold comfort" letters required by or
incident to such performance), (vi) Securities Act liability insurance, if the
Company so





                                      -11-
<PAGE>   12
desires such insurance, and (vii) fees and expenses of all other persons
retained by the Company.  In addition, the Company shall pay its internal
expenses (including, without limitation, all salaries and expenses of its
officers and employees performing legal or accounting duties), the expense of
an annual audit, and the fees and expenses incurred in connection with the
listing of the securities to be registered on any securities exchange.
Notwithstanding the foregoing or anything in this Agreement to the contrary,
each Holder shall pay all underwriting discounts and commissions of any
underwriters with respect to any Transfer Restricted Securities sold by it.

                 (b)      In connection with any registration hereunder, the
Company shall reimburse the Holders of the Transfer Restricted Securities being
registered or tendered for in such registration for the fees and disbursements
of not more than one firm of attorneys representing the selling Holders (in
addition to any local counsel), which firm shall be chosen by the Holders of a
majority in aggregate principal amount of the Transfer Restricted Securities.
Orrick, Herrington & Sutcliffe shall be Special Counsel for all purposes hereof
unless and until another Special Counsel shall have been selected by a majority
in aggregate principal amount of the Transfer Restricted Securities and notice
hereof shall have been given to the Company.

                 5.       Indemnification.

                 (a)      The Company agrees to indemnify and hold harmless (i)
each of the Initial Purchasers, (ii) each Holder of Transfer Restricted
Securities, (iii) each person, if any, who controls (within the meaning of
Section 15 of the Securities Act or Section 20 of the Exchange Act) any of the
foregoing (any of the persons referred to in this clause (iii) being
hereinafter referred to as a "controlling person"), and (iv) the respective
officers, directors, partners, employees, representatives and agents of the
Initial Purchasers, each Holder of Transfer Restricted Securities, or any
controlling person (any person referred to in clause (i), (ii), (iii) or (iv)
may hereinafter be referred to as an "Indemnified Person"), from and against
any and all losses, claims, damages, liabilities, expenses and judgments caused
by any untrue statement or alleged untrue statement of a material fact
contained in any Registration Statement, Prospectus or form of Prospectus or in
any amendment or supplement thereto or in any preliminary Prospectus, or caused
by any omission or alleged omission to state therein a material fact required
to be stated therein or necessary to make the statements therein (in the case
of any Prospectus or form of Prospectus or supplement thereto, in the light of
the circumstances under which they were made) not misleading, except insofar as
such losses, claims, damages, liabilities, expenses or judgments are caused by
any such untrue statement or omission or alleged untrue statement or omission
based upon information relating to any Indemnified Person furnished in writing
to the Company by or on behalf of such Indemnified Person expressly for use
therein; provided that the foregoing indemnity with respect to any preliminary
Prospectus shall not inure to the benefit of any Indemnified Person from whom
the person asserting such losses, claims, damages, liabilities, expenses and
judgments purchased securities if such untrue statement or omission or alleged
untrue statement or omission made in such preliminary Prospectus is eliminated
or remedied in the Prospectus and a copy of the Prospectus shall not have been
furnished to such person in a timely manner, unless such Prospectus was not
furnished because the Company failed to





                                      -12-
<PAGE>   13
provide the Indemnified Person with sufficient copies of such corrected
Prospectus within the time period required.

                 (b)      In case any action shall be brought against any
Indemnified Person, based upon any Registration Statement or any such
Prospectus or any amendment or supplement thereto and with respect to which
indemnity may be sought against the Company, such Indemnified Person shall
promptly notify the Company in writing and the Company shall assume the defense
thereof, including the employment of counsel reasonably satisfactory to such
Indemnified Person and payment of all fees and expenses.  Any Indemnified
Person shall have the right to employ separate counsel in any such action and
participate in the defense thereof, but the fees and expenses of such counsel
shall be at the expense of such Indemnified Person, unless (i) the employment
of such counsel shall have been specifically authorized in writing by the
Company, (ii) the Company shall have failed to assume the defense and employ
counsel or (iii) such Indemnified Person or Persons shall have been advised by
counsel that there may be a conflict between the positions of the indemnifying
party or parties and of the indemnified party or parties in conducting the
defense of such action or proceeding or that there may be legal defenses
available to such Indemnified Person or Persons different from or in addition
to those available to the indemnifying party or parties (in which case the
Company shall not have the right to assume the defense of such action on behalf
of such Indemnified Person, it being understood, however, that the Company
shall not, in connection with any one such action or separate but substantially
similar or related actions in the same jurisdiction arising out of the same
general allegations or circumstances, be liable for the fees and expenses of
more than one separate firm of attorneys (in addition to any local counsel) for
all such Indemnified Persons, which firm shall be designated in writing by such
Indemnified Persons, and that all such fees and expenses shall be reimbursed as
they are incurred).  The Company shall not be liable for any settlement of any
such action effected without its written consent but if settled with the
written consent of the Company, the Company agrees to indemnify and hold
harmless any Indemnified Person from and against any loss or liability by
reason of such settlement.  No indemnifying party shall, without the prior
written consent of the indemnified party, effect any settlement of any pending
or threatened proceeding in respect of which any indemnified party is or could
have been a party and indemnity could have been sought hereunder by such
indemnified party, unless such settlement includes an unconditional release of
such indemnified party from all liability on claims that are the subject matter
of such proceeding.

                 (c)      In connection with any Registration Statement in
which the Holder of Transfer Restricted Securities is participating, such
Holder of Transfer Restricted Securities agrees, severally and not jointly, to
indemnify and hold harmless the Company, its directors, its officers and any
person controlling the Company within the meaning of Section 15 of the
Securities Act or Section 20 of the Exchange Act, to the same extent as the
foregoing indemnity from the Company to each Indemnified Person but only with
reference to information relating to such Indemnified Person furnished in
writing by or on behalf of such Indemnified Person expressly for use in such
Registration Statement.  In case any action shall be brought against the
Company, any of its directors, any such officer or any person controlling the
Company based on such Registration Statement and in respect of which





                                      -13-
<PAGE>   14
indemnity may be sought against any Indemnified Person, the Indemnified Person
shall have the rights and duties given to the Company (except that if the
Company shall have assumed the defense thereof, such Indemnified Person shall
not be required to do so, but may employ separate counsel therein and
participate in defense thereof but the fees and expenses of such counsel shall
be at the expense of such Indemnified Person), and the Company, its directors,
any such officers and any person controlling the Company shall have the rights
and duties given to the Indemnified Person, by Section 5(b) hereof.

                 (d)      If the indemnification provided for in this Section 5
is unavailable to an indemnified party in respect of any losses, claims,
damages, liabilities, expenses or judgments referred to therein, then each
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, expenses and judgments (i) in
such proportion as is appropriate to reflect the relative benefits received by
the Company on the one hand and each Indemnified Person on the other hand from
the offering of the Transfer Restricted Securities or (ii) if the allocation
provided by clause (i) above is not permitted by applicable law, in such
proportion as is appropriate to reflect not only the relative benefits referred
to in clause (i) above but also the relative fault of the Company and each such
Indemnified Person in connection with the statements or omissions which
resulted in such losses, claims, damages, liabilities, expenses or judgments,
as well as any other relevant equitable considerations.  The relative fault of
the Company and each such Indemnified Person shall be determined by reference
to, among other things, whether the untrue or alleged untrue statement of a
material fact or the omission to state a material fact relates to information
supplied by the Company or such Indemnified Person and the parties' relative
intent, knowledge, access to information and opportunity to correct or prevent
such statement or omission.

                 The Company and the Initial Purchasers agree that it would not
be just and equitable if contribution pursuant to this Section 5(d) were
determined by pro rata allocation (even if the Indemnified Person were treated
as one entity for such purpose) or by any other method of allocation which does
not take account of the equitable considerations referred to in the immediately
preceding paragraph.  The amount paid or payable by an indemnified party as a
result of the losses, claims, damages, liabilities, expenses or judgments
referred to in the immediately preceding paragraph shall be deemed to include,
subject to the limitations set forth above, any legal or other expenses
reasonably incurred by such indemnified party in connection with investigating
or defending any such action or claim.  Notwithstanding the provisions of this
Section 5, no Indemnified Person shall be required to contribute any amount in
excess of the amount by which the total net profit received by it in connection
with the sale of the Transfer Restricted Securities pursuant to this Agreement
exceeds the amount of any damages which such Indemnified Person has otherwise
been required to pay by reason of such untrue or alleged untrue statement or
omission or alleged omission.  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.  The Indemnified Persons' obligations to contribute pursuant
to this Section 5(d) are several in proportion to the respective amount of





                                      -14-
<PAGE>   15
Transfer Restricted Securities included in and sold pursuant to any such
Registration Statement by each Indemnified Person and not joint.

                 (e)      The agreements contained in this Section 5 shall
survive the sale of the Transfer Restated Securities pursuant to any
Registration Statement and shall remain in full force and effect, regardless of
any investigation made by or on behalf of any Indemnified Person.

                 6.       Rules 144 and 144A.

                 The Company shall use all reasonable efforts to file the
reports required to be filed by it under the Securities Act and the Exchange
Act in a timely manner and, if at any time it is not required to file such
reports but in the past had been required to or did file such reports, it will,
upon the request of any Holder, make available other information as required
by, and so long as necessary to permit sales of, its Transfer Restricted
Securities pursuant to Rule 144 and Rule 144A.  Notwithstanding the foregoing,
nothing in this Section 6 shall be deemed to require the Company to register
any of its securities pursuant to the Exchange Act.

                 7.       Underwritten Registrations.

                 If any of the Transfer Restricted Securities covered by any
Shelf Registration Statement are to be sold in an underwritten offering, the
investment banker or investment bankers and manager or managers that will
administer the offering will be investment bankers of recognized national
standing selected by the Holders of a majority in aggregate principal amount of
such Transfer Restricted Securities included in such offering, subject to the
consent of the Company (which will not be unreasonably withheld or delayed).

                 No person may participate in any underwritten registration
hereunder unless such person (i) agrees to sell such person's Transfer
Restricted Securities on the basis reasonably provided in any underwriting
arrangements approved by the persons entitled hereunder to approve such
arrangements and (ii) completes and executes all questionnaires, powers of
attorney, indemnities, underwriting agreements and other documents reasonably
required under the terms of such underwriting arrangements.

                 8.       Miscellaneous.

                 (a)      Remedies.  In the event of a breach by the Company,
or by a Holder of Transfer Restricted Securities, of any of their obligations
under this Agreement, each Holder of Transfer Restricted Securities or the
Company, respectively, in addition to being entitled to exercise all rights
granted by law, including recovery of damages, will be entitled to specific
performance of its rights under this Agreement.  The Company and each Holder of
Transfer Restricted Securities agree that monetary damages would not be
adequate compensation for any loss incurred by reason of a breach by it of any
of the provisions of this Agreement and hereby further agree that, in the event
of any action for specific





                                      -15-
<PAGE>   16
performance in respect of such breach, they shall waive the defense that a
remedy at law would be adequate.

                 (b)      No Inconsistent Agreements.  The Company shall not
enter into any agreement with respect to its securities that is inconsistent
with the rights granted to the holders of Transfer Restricted Securities in
this Agreement or otherwise conflicts with the provisions hereof.  The Company
is not currently a party to any agreement granting any registration rights with
respect to any of its securities to any person which conflicts with the
Company's obligations hereunder or gives any other party the right to include
any securities in any Registration Statement filed pursuant hereto, except for
such rights and conflicts as have been irrevocably waived.  Without limiting
the generality of the foregoing, without the written consent of the Holders of
a majority in aggregate principal amount of the Transfer Restricted Securities,
the Company shall not grant to any person the right to request it to register
any of its securities under the Securities Act unless the rights so granted are
subject in all respect to the prior rights of the holders of Transfer
Restricted Securities set forth herein, and are not otherwise in conflict or
inconsistent with the provisions of this Agreement.

                 (c)      No Adverse Action Affecting the Transfer Restricted
Securities.  The Company will not take any action with respect to the Transfer
Restricted Securities which would adversely affect the ability of any of the
Holders of Transfer Restricted Securities to include such Transfer Restricted
Securities in a registration undertaken pursuant to this Agreement.

                 (d)      No Piggyback on Registrations.  The Company shall not
grant to any of its security holders (other than the Holders of Transfer
Restricted Securities in such capacity) the right to include any of its
securities in any Shelf Registration Statement other than Transfer Restricted
Securities.

                 (e)      Amendments and Waivers.  The provisions of this
Agreement, including the provisions of this sentence, may not be amended,
modified or supplemented, and waivers or consents to departures from the
provisions hereof, may not be given, without the written consent of the Holders
of a majority in aggregate principal amount of the Transfer Restricted
Securities.  Notwithstanding the foregoing, a waiver or consent to depart from
the provisions hereof with respect to a matter that relates exclusively to the
rights of Holders of Transfer Restricted Securities whose securities are being
sold pursuant to a Registration Statement and that does not directly or
indirectly affect the rights of other Holders of Transfer Restricted Securities
may be given by Holders of a majority in aggregate principal amount of the
Transfer Restricted Securities being sold by such Holders pursuant to such
Registration Statement; provided, however, that the provisions of this sentence
may not be amended, modified, or supplemented except in accordance with the
provisions of the immediately preceding sentence.

                 (f)      Notices.  All notices and other communications
provided for herein shall be made in writing by hand-delivery, next-day air
courier, certified first-class mail, return receipt requested or telecopy:





                                      -16-
<PAGE>   17
                          (i)     if to a Holder of Transfer Restricted
Securities, to the address of such Holder as it appears in the Note or Common
Stock register of the Company, as applicable; and

                     (ii)         if to the Company, to:

                                  S3 Incorporated
                                  2770 San Tomas Expressway
                                  Santa Clara, California 95051
                                  Attention:  Chief Financial Officer
                                  Telecopy No.:  (408) 980-5445

                                  with a copy to:

                                  Pillsbury Madison & Sutro LLP
                                  2700 Sand Hill Road
                                  Menlo Park, California 94025
                                  Attention:  Jorge del Calvo, Esq.
                                  Telecopy No:  (415) 233-4545

                    (iii)         if to the Special Counsel, to:

                                  Orrick, Herrington & Sutcliffe LLP
                                  Old Federal Reserve Bank Building
                                  400 Sansome Street
                                  San Francisco, California 94111
                                  Attention:  M. Peter Lillevand, Esq.
                                  Telecopy No.:  (415) 773-5759

or such other Special Counsel at such other address and telecopy number as a
majority in aggregate principal amount of the Transfer Restricted Securities
shall have given notice to the Company as contemplated by Section 4(b) hereof.

                 Except as otherwise provided in this Agreement, all such
communications shall be deemed to have been duly given, when delivered by hand,
if personally delivered; one Business Day after being timely delivered to a
next-day air courier, five Business Days after being deposited in the mail,
postage prepaid, if mailed; and when receipt is acknowledged by the recipient's
telecopier machine, if telecopied.

                 (g)      Successors and Assigns.  This Agreement shall inure
to the benefit of and be binding upon the successors and permitted assigns of
each of the parties and shall inure to the benefit of each existing and future
Holder of Transfer Restricted Securities.  The Company may not assign its
rights or obligations hereunder without the prior written consent of each
Holder of Transfer Restricted Securities, other than by operation of law
pursuant to a merger or consolidation to which the Company is a party.  In the
event the Notes become convertible into common stock of another person pursuant
to Section 15.6 of





                                      -17-
<PAGE>   18
the Indenture, the Company shall cause such person to assume the Company's
obligations hereunder.

                 (h)      Counterparts.  This Agreement may be executed in any
number of counterparts and by the parties hereto in separate counterparts each
of which when so executed shall be deemed to be an original and all of which
taken together shall constitute one and the same Agreement.

                 (i)      Governing Law; Submission to Jurisdiction.

                 THIS AGREEMENT SHALL BE GOVERNED BY AND CONSTRUED IN
ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK, AS APPLIED TO CONTRACTS MADE
AND PERFORMED WITHIN THE STATE OF NEW YORK WITHOUT REGARD TO PRINCIPLES OF
CONFLICTS OF LAW.  THE COMPANY HEREBY IRREVOCABLY SUBMITS TO THE JURISDICTION
OF ANY NEW YORK STATE COURT SITTING IN THE BOROUGH OF MANHATTAN IN THE CITY OF
NEW YORK OR ANY FEDERAL COURT SITTING IN THE BOROUGH OF MANHATTAN IN THE CITY
OF NEW YORK IN RESPECT OF ANY SUIT, ACTION OR PROCEEDING ARISING OUT OF OR
RELATING TO THIS AGREEMENT, AND IRREVOCABLY ACCEPTS FOR ITSELF AND IN RESPECT
OF ITS PROPERTY, GENERALLY AND UNCONDITIONALLY, JURISDICTION OF THE AFORESAID
COURTS.  THE COMPANY IRREVOCABLY WAIVES, TO THE FULLEST EXTENT IT MAY
EFFECTIVELY DO SO UNDER APPLICABLE LAW, ANY OBJECTION THAT IT MAY NOW OR
HEREAFTER HAVE TO THE LAYING OF THE VENUE OF ANY SUCH SUIT, ACTION OR
PROCEEDING BROUGHT IN ANY SUCH COURT AND ANY CLAIM THAT ANY SUCH SUIT, ACTION
OR PROCEEDING BROUGHT IN ANY SUCH COURT HAS BEEN BROUGHT IN AN INCONVENIENT
FORUM.

                 (j)      Severability.  The remedies provided herein are
cumulative and not exclusive of any remedies provided by law. If any term,
provision, covenant or restriction of this Agreement is held by a court of
competent jurisdiction to be invalid, illegal, void or unenforceable, the
remainder of the terms, provisions, covenants and restrictions set forth herein
shall remain in full force and effect and shall in no way be affected, impaired
or invalidated, and the parties hereto shall use their best efforts to find and
employ an alternative means to achieve the same or substantially the same
result as that contemplated by such term, provision, covenant or restriction.
It is hereby stipulated and declared to be the intention of the parties that
they would have executed the remaining terms, provisions, covenants and
restrictions without including any of such that may be hereafter declared
invalid, illegal, void or unenforceable.

                 (k)      Headings.  The headings in this Agreement are for
convenience of reference only and shall not limit or otherwise affect the
meaning hereof.  All references made in this Agreement to "Section" and
"paragraph" refer to such Section or paragraph of this Agreement, unless
expressly stated otherwise.





                                      -18-
<PAGE>   19
                 (l)      Attorneys' Fees.  In any action or proceeding brought
to enforce any provision of this Agreement, or where any provision hereof is
validly asserted as a defense, the prevailing party, as determined by the
court, shall be entitled to recover its reasonable attorneys' fees in addition
to any other available remedy.

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


                                                   S3 INCORPORATED



                                                   By:                         
                                                   ------------------------




                                                   LEHMAN BROTHERS INC.
                                                   PAINEWEBBER INCORPORATED
                                                   COWEN & COMPANY

                                                   BY LEHMAN BROTHERS INC.



                                                   By:                         
                                                       ------------------------
                                                        Authorized Signatory






                                      -19-