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                                                                    EXHIBIT 10.1

                  AMENDMENT NO. 1 TO VOLUME PURCHASE AGREEMENT

This Amendment No. 1 ("Amendment"), with an effective date of October 5, 2001,
to the Volume Purchase Agreement (as amended, "VPA") dated as of April 8, 1999
between Western Digital Corporation, a Delaware corporation ("WDC"), and Komag,
Inc., a Delaware corporation ("Komag"), is made by and among WDC, Komag and
Komag USA (Malaysia) Sdn., a Malaysia unlimited liability company ("Komag
Malaysia").

                                    RECITALS

A.      WDC and Komag entered into the VPA whereby Komag and/or Komag Malaysia
        would supply WDC's media requirements for a three year period.

B.      As permitted by Section 12.4 of the VPA, Komag and Komag Malaysia
        entered into an Assignment of Rights and Delegation of Duties under the
        VPA, with an effective date of December 12, 1999, pursuant to which
        Komag assigned to Komag Malaysia its rights and delegated the
        performance of its duties under the VPA.

C.      WDC wishes to accept Komag Malaysia as the assignee of Komag and its
        rights and obligations under the VPA, and WDC, Komag and Komag Malaysia
        wish to amend the VPA to extend its term and to make certain other
        changes.

D.      On August 24, 2001, Komag filed a voluntary petition under chapter 11 of
        title 11 of the United States Code (the "Bankruptcy Code"), thereby
        commencing Case No. 01-54143-JRG currently pending before the United
        States Bankruptcy Court for the Northern District of California (the
        "Bankruptcy Court"). Komag currently is managing its affairs as a debtor
        in possession pursuant to sections 1107 and 1108 of the Bankruptcy Code.

                                    AGREEMENT

FOR GOOD AND VALUABLE CONSIDERATION, the receipt of which is hereby
acknowledged, the parties agree as follows:

1.      In the table at the end of section 1.19.1 of the VPA, the entry in the
        bottom row, middle column, shall be amended in its entirety to read as
        follows:

        "Until the end of the term of the agreement as defined in section 9.1"

2.      In the table at the end of section 4.1 of the VPA, the entry in the
        bottom row, middle column, shall be amended in its entirety to read as
        follows:

        "Until the end of the term of the agreement as defined in section 9.1"

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3.      In the table at the end of section 4.1 of the VPA, the heading in the
        top row, right column shall be amended in its entirety to read as
        follows:

        "PURCHASE REQUIREMENTS DURING EACH 12 MONTH PERIOD"

4.      Section 9.1 of the VPA shall be amended in its entirety to read as
        follows:

        "This VPA shall continue in force for an initial term of six years from
        the Effective Date and shall be automatically renewed for successive two
        (2) year periods thereafter; provided, however, that either party may
        elect to not renew this VPA by notifying the other party no later than
        one year prior to the expiration of the initial term or any succeeding
        term of its intention to not have the VPA automatically renewed at the
        expiration of such term."

5.      All other terms of the VPA shall remain the same.

6.      Komag Malaysia, as the assignee of Komag under the VPA, hereby agrees to
        be bound by all of the terms and conditions of and to perform the
        obligations of Komag under the VPA, as amended. Western Digital hereby
        acknowledges Komag's assignment of its rights and delegation of its
        performance under the VPA to Komag Malaysia and accepts Komag Malaysia
        as the assignee of Komag and all its rights and obligations under the
        VPA, as amended; provided, however, that Komag agrees to continue to
        provide its personnel and resources in support of Komag Malaysia's
        qualification obligations under the VPA.

        IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
executed by their duly authorized representatives as of the Effective Date.


        Western Digital Corporation             Komag, Inc.

        By:      ______________________         By:      ______________________

        Name:    ______________________         Name:    ______________________

        Title:   ______________________         Title:   ______________________




                                                Komag USA (Malaysia) Sdn.


                                                By:      ______________________

                                                Name:    ______________________

                                                Title:   ______________________



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