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                                                                  EXHIBIT 3(i).4

                            CERTIFICATE OF AMENDMENT

                                       OF

                      RESTATED CERTIFICATE OF INCORPORATION

                                       OF

                                 S3 INCORPORATED



         S3 Incorporated, a corporation organized and existing under and by
virtue of the General Corporation Law of the State of Delaware, DOES HEREBY
CERTIFY:

         FIRST: That the Board of Directors of said corporation at a regular
meeting of said Board held on January 14, 1999, duly adopted a resolution
proposing and declaring advisable the following amendment to Article IV of the
Restated Certificate of Incorporation of said corporation:


                                   ARTICLE IV

         A. Number and Classes of Stock. This Corporation is authorized to issue
two classes of stock, designated "Preferred Stock" and "Common Stock,"
respectively. The total number of shares which this Corporation shall have
authority to issue is one hundred twenty-five million (125,000,000). The number
of shares of Common Stock authorized to be issued is one hundred twenty million
(120,000,000) with a par value of $0.0001. The number of shares of Preferred
Stock authorized to be issued is five million (5,000,000) with a par value of
$0.0001. The number of authorized shares of Common Stock or Preferred Stock may
be increased or decreased (but not below the number of shares thereof then
outstanding) by the affirmative vote of the holders of a majority of the then
outstanding shares of Common Stock, without a vote of the holders of the
Preferred Stock, or of any series thereof, unless a vote of any such Preferred
Stock holders is required pursuant to the provisions established by the Board of
Directors of this Corporation (the "Board of Directors") in the resolution or
resolutions providing for the issue of such Preferred Stock, and if such holders
of such Preferred Stock are so entitled to vote thereon, then, except as may
otherwise be set forth in this Restated Certificate of Incorporation, the only
stockholder approval required shall be the affirmative vote of a majority of the
combined voting power of the Common Stock and the Preferred Stock so entitled to
vote.

         B. Preferred Stock. The Preferred Stock may be issued from time to time
in one or more series. The Board of Directors is expressly authorized to provide
for the issue, in one or more series, of all or any of the remaining shares of
Preferred Stock and, in the resolution or resolutions providing for such issue,
to establish for each such series the number of its shares, the voting powers,
full or limited, of the shares of such series, or that such shares shall have no
voting powers, and the designations, preferences and relative, participating,
optional or other special rights of the shares of such series, and the
qualifications, limitations or restrictions 

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thereof. The Board of Directors is also expressly authorized (unless forbidden
in the resolution or resolutions providing for such issue) to increase or
decrease (but not below the number of shares of the series then outstanding) the
number of shares of any series subsequent to the issuance of shares of that
series. In case the number of shares of any such series shall be so decreased,
the shares constituting such decrease shall resume the status that they had
prior to the adoption of the resolution originally fixing the number of shares
of such series.

         C.       Common Stock.

         1. Relative Rights of Preferred Stock and Common Stock. All
preferences, voting powers, relative, participating, optional or other special
rights and privileges, and qualifications, limitations or restrictions of the
Common Stock are expressly made subject and subordinate to those that may be
fixed with respect to any shares of the Preferred Stock.

         2. Voting Rights. Except as otherwise required by law or this Restated
Certificate of Incorporation, each holder of Common Stock shall have one vote in
respect of each share of stock held by such holder of record on the books of the
corporation for the election of directors and on all matters submitted to a vote
of stockholders of the corporation.

         3. Dividends. Subject to the preferential rights of the Preferred
Stock, the holders of shares of Common Stock shall be entitled to receive, when
and if declared by the Board of Directors, out of the assets of this Corporation
which are by law available therefor, dividends payable either in cash, in
property or in shares of capital stock.

         4. Dissolution, Liquidation or Winding Up. In the event of any
dissolution, liquidation or winding up of the affairs of this Corporation, after
distribution in full of the preferential amounts, if any, to be distributed to
the holders of shares of the Preferred Stock, holders of Common Stock shall be
entitled, unless otherwise provided by law or this Restated Certificate of
Incorporation, to receive all of the remaining assets of the corporation of
whatever kind available for distribution to stockholders ratably in proportion
to the number of shares of Common Stock held by them respectively.

         SECOND: Pursuant to a special meeting and vote of stockholders, the
stockholders have given consent to said amendment in accordance with the
provisions of Section 242 of the General Corporation Law of Delaware.

         THIRD: That the aforesaid amendment was duly adopted in accordance with
the applicable provisions of Section 242 of the General Corporation Law of the
State of Delaware.


         IN WITNESS WHEREOF, S3 Incorporated has caused this certificate to be
signed this 25th day of February, 1999.


                             By   /s/ Walter D. Amaral
                                  -------------------------------
                                  Walter D. Amaral
                                  Senior Vice President and
                                  Chief Financial Officer


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