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                                                                  EXHIBIT 3(1).5


                            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 (the "General
Corporation Law"), DOES HEREBY CERTIFY:

        FIRST: That the Board of Directors of the corporation has duly adopted a
resolution proposing and declaring advisable an amendment to the Restated
Certificate of Incorporation pursuant to which Section A of Article IV thereof
is hereby amended to read in its entirety as follows:

               "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 eighty million
        (180,000,000). The number of shares of Common Stock authorized to be
        issued is one hundred seventy-five million (175,000,000) 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 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."

        SECOND: Pursuant to a special meeting called and held upon notice in
accordance with Section 222 of the General Corporation Law, the stockholders
have voted in favor of said amendment in accordance with the provisions of
Section 242 of the General Corporation Law.

        THIRD: The aforesaid amendment was duly adopted in accordance with
Section 242 of the General Corporation Law.


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        IN WITNESS WHEREOF, the corporation has caused this Certificate of
Amendment to be executed by its duly authorized officer, this ___th day of
September, 1999.

                                     S3 INCORPORATED

                                     By
                                          -------------------------------------
                                          Kenneth F. Potashner
                                          President and Chief Executive Officer


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