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                                                                     EXHIBIT 4.2

                            CERTIFICATE OF AMENDMENT
                                       OF
                          CERTIFICATE OF INCORPORATION
                                       OF
                           WESTERN DIGITAL CORPORATION

         Western Digital Corporation, a corporation organized and existing under
the laws of the State of Delaware (the "Corporation"), hereby certifies as
follows:

         1.       The name of the Corporation is Western Digital Corporation.

         2.       The Amended and Restated Certificate of Incorporation of the
Corporation is hereby amended by striking out Article IV thereof in its entirety
and by substituting in lieu of said Article the following new Article:

                                  "ARTICLE IV

                            AUTHORIZED CAPITAL STOCK

                  This corporation shall be authorized to issue two classes of
         shares of stock to be designated, respectively, "Preferred Stock" and
         "Common Stock"; the total number of shares which this corporation shall
         have authority to issue is Four Hundred Fifty-Five Million
         (455,000,000); the total number of shares of Preferred Stock shall be
         Five Million (5,000,000) and each such share shall have a par value of
         one cent ($0.01); and the total number of shares of Common Stock shall
         be Four Hundred Fifty Million (450,000,000) and each such share shall
         have a par value of one cent ($0.01).

                  The shares of Preferred Stock may be issued from time to time
         in one or more series. The Board of Directors is hereby vested with
         authority to fix by resolution or resolutions the designations and the
         powers, preferences and relative, participating, optional or other
         special rights, and qualifications, limitations or restrictions
         thereof, including without limitation the dividend rate, conversion
         rights, redemption price and liquidation preference, of any series of
         shares of Preferred Stock, and to fix the number of shares constituting
         any such series, and to increase or decrease the number of shares of
         any such series (but not below the number of shares thereof then
         outstanding). In case the number of shares of any such series shall be
         so decreased, the shares constituting such decrease shall resume the
         status which they had prior to the adoption of the resolution or
         resolutions originally fixing the number of shares of such series."

         3.       Pursuant to resolutions adopted at a meeting of the Board of
Directors of the Corporation approving the proposed amendment to the Certificate
of Incorporation of the
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Corporation, declaring the amendment to be advisable and calling a meeting of
the stockholders of the Corporation for consideration thereof, the annual
meeting of the stockholders of the Corporation was duly called and held, upon
notice in accordance with Section 222 of the General Corporation Law of the
State of Delaware, at which meeting the necessary number of shares as required
by statute were voted in favor of the amendment.

         4.       The amendment of the Amended and Restated Certificate of
Incorporation of the Corporation herein certified has been duly adopted in
accordance with the provisions of Section 242 of the General Corporation Law of
the State of Delaware.

         IN WITNESS WHEREOF, the Corporation has caused this Certificate of
Amendment to be executed by its authorized officer on the 7th day of January,
2002.

                                        WESTERN DIGITAL CORPORATION,
                                        a Delaware corporation

                                        /s/ Michael A. Cornelius
                                        ----------------------------------------
                                        Michael A. Cornelius
                                        Vice President, Law and Administration
                                        and Secretary


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