EXHIBIT 4.2(b)

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                        ADVANCED MICRO DEVICES, INC.

                                   ISSUER

                      11% Senior Secured Notes due 2003


                  ________________________________________

                        FIRST SUPPLEMENTAL INDENTURE

                        Dated as of January 13, 1999

                  ________________________________________


                   United States Trust Company of New York

                                   TRUSTEE

                                        



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                        FIRST SUPPLEMENTAL INDENTURE
                        ----------------------------

          FIRST SUPPLEMENTAL INDENTURE, dated as of January 13, 1999, by and
between Advanced Micro Devices, Inc., a Delaware corporation (the "Company"),
and United States Trust Company of New York, as trustee (the "Trustee").

                                  RECITALS
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          A.    Pursuant to that certain Indenture (the "Indenture"), dated as
of August 1, 1996 by and between the Company and the Trustee, the Company
issued and sold $400,000,000 in aggregate principal amount of its 11% Senior
Secured Notes due 2003 (the "Notes").

          B.    The Company is considering divesting all or a portion of its
interest in the programmable logic device ("PLD") business currently operated
by Vantis Corporation, a Delaware corporation and wholly owned subsidiary of
the Company ("Vantis"), through (i) the issuance of equity interests or other
rights representing no more than 15% of the outstanding equity interests of
Vantis to certain directors, officers, employees and other individuals
providing services to Vantis (the "Potential Employee Issuance") and/or (ii)
an initial public offering of Vantis common stock or the issuance or exchange
of Vantis common stock in connection with a merger, sale or other disposition
of Vantis (collectively with the Potential Employee Issuance, the "Potential
PLD Divestment").

          C.    The Indenture currently prohibits (i) the sale of 35% or less
of the Company's equity interests in Vantis in connection with an initial
public offering of Vantis, (ii) the Potential Employee Issuance, including the
repurchase by the Company or Vantis of equity interests of Vantis issued
pursuant thereto, (iii) the issuance or exchange of Vantis common stock in
connection with a merger of Vantis without compliance with certain financial
covenants set forth in the Indenture, and (iv) in most circumstances, the
retention by the Company of equity interests in any former subsidiary without
compliance with certain financial limitations set forth in the Indenture. The
foregoing prohibitions (collectively, the "Original Divestment Covenants")
would, in certain circumstances, prohibit or restrict the Potential PLD
Divestment.

          D.    The Company and the Trustee now desire to amend, modify and
supplement the Indenture, in the respects hereinafter set forth, to
specifically permit the Potential PLD Divestment without regard to the
Original Divestment Covenants.

          E.    In accordance with Section 9.02 of the Indenture, the holders
of at least a majority in principal amount of the outstanding Notes have
consented to the amendments to the Indenture set forth in this First
Supplemental Indenture.

          NOW, THEREFORE, in consideration of the foregoing and in consideration
of the mutual covenants herein contained, the parties hereto make this First
Supplemental Indenture intending to be legally bound hereby.

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          Section 1.   Incorporation of the Indenture.  Except as specifically 
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amended hereby, the terms and conditions of the Indenture remain in full force
and effect as if fully rewritten herein.

          Section 2.   Amendment to Section 1.01 of the Indenture.  Section 
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1.01 of the Indenture is hereby amended by deleting the defined term "PLD
Subsidiary" and inserting in lieu thereof the definition provided below:

          "PLD Subsidiary" means Vantis Corporation, a Delaware corporation
     ("Vantis"), any Subsidiary of the Company which holds all of the Equity
     Interests of Vantis, and any Subsidiary of either of the foregoing which
     operates the business (other than the bipolar programmable logic device
     business) operated by the Company's Programmable Logic Division as of the
     Issue Date.

          Section 3.   Amendment to Section 4.11 of the Indenture.  Section 
                       ------------------------------------------  
4.11 of the Indenture is hereby amended by deleting the text of said section
in its entirety and inserting in lieu thereof the following text:

          The Company (i) will not, and will not permit any Wholly Owned
  Restricted Subsidiary of the Company to, transfer, convey, sell, lease or
  otherwise dispose of any Capital Stock of any Wholly Owned Restricted
  Subsidiary of the Company to any Person (other than the Company or a Wholly
  Owned Restricted Subsidiary of the Company), unless (a) such transfer,
  conveyance, sale, lease or other disposition is of all the Capital Stock of
  such Wholly Owned Restricted Subsidiary and (b) the cash Net Proceeds from
  such transfer, conveyance, sale, lease or other disposition are applied in
  accordance with Section 4.10(a) hereof and (ii) will not permit any Wholly
  Owned Restricted Subsidiary of the Company to issue any of its Equity
  Interests (other than, if necessary, shares of its Capital Stock constituting
  directors' qualifying shares) to any Person other than to the Company or a
  Wholly Owned Restricted Subsidiary of the Company.  Notwithstanding the
  foregoing, nothing in this Section 4.11 or any other provision of this
  Indenture shall in any way prohibit or restrict (x) the Company from selling
  more than 35% of its Equity Interest in any Wholly Owned Restricted Subsidiary
  other than the PLD Subsidiary in connection with the Initial Public Offering
  of such Wholly Owned Restricted Subsidiary, provided 100% of the net proceeds
  from such Initial Public Offering received by the Company are in the form of
  cash and all such proceeds are applied in accordance with Section 4.10(a)
  hereof, (y) the Company or any of its Wholly Owned Restricted Subsidiaries
  from selling or issuing Equity Interests or other rights in the PLD Subsidiary
  (I) in connection with the Initial Public Offering of the PLD Subsidiary,
  provided that 100% of the net proceeds from such Initial Public Offering
  received by the Company or any of its Subsidiaries are in the form of cash and
  all such proceeds are applied in accordance with Section 4.10(a) hereof, or
  (II) to directors, officers, employees, consultants and advisors of the PLD
  Subsidiary; provided that, in the case of this clause (y)(II), such Equity
  Interests or other rights shall represent no more than 15% of the outstanding
  Equity Interests of the PLD Subsidiary; Equity Interests or other rights
  issued or sold pursuant to this clause (y)(II) may, at the option of the
  Company or any of its 

                                       2

 
  Subsidiaries, be repurchased, redeemed, acquired or retired for value by the
  Company or such Subsidiaries at any time and in any manner (including by
  means of an exchange for Equity Interests of the Company), or (z) the
  issuance and exchange of Equity Interests (other than Disqualified Stock) of
  the Company's PLD Subsidiary (as defined herein) in connection with the
  merger, sale, transfer, lease or other disposition of the PLD Subsidiary to,
  with or into any Person, provided the Company and the PLD Subsidiary or the
  Person surviving such a merger, sale, transfer, lease or other disposition
  shall enter into a new agreement substantially in the form of, or a written
  agreement affirming, the Wafer Fabrication Agreement by and between the
  Company and the PLD Subsidiary in effect during the full fiscal-quarter
  immediately preceding the announcement of such merger, sale, transfer, lease
  or other disposition of the PLD Subsidiary. Notwithstanding any other
  provision of this Indenture, Equity Interests (i) retained by the Company or
  any of its Subsidiaries in any former Subsidiary after any issuance, sale,
  exchange or other disposition permitted by this Section 4.11 or (ii)
  received by the Company or any of its Subsidiaries in connection with a
  merger, sale, transfer, lease or other disposition permitted by this Section
  4.11, shall not be considered Investments under this Indenture.

          Section 4.   Counterparts.  This First Supplemental Indenture may be 
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executed on several counterparts, each of which shall be deemed an original
but shall constitute one and the same instrument.

          Section 5.   Effectiveness.  This First Supplemental Indenture shall 
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become effective as of the date first written above.

          Section 6.   Headings.  The Section references herein are for 
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convenience of reference only and shall not affect the construction hereof.


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                                 SIGNATURES
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          IN WITNESS WHEREOF, the parties hereto have caused this First
Supplemental Indenture to be duly executed by their duly authorized officers and
attested, all as of the day and year first above written.



                        ADVANCED MICRO DEVICES, INC.


                        By:   /s/ Francis P. Barton
                           ------------------------
                        Name:  Francis P. Barton
                             ------------------- 
                        Title: Senior Vice President and Chief Financial Officer
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                        UNITED STATES TRUST COMPANY OF NEW YORK,
                        as Trustee


                        By:  /s/ Louis P. Young
                           --------------------
                        Name:    Louis P. Young
                             ------------------
                        Title:  Vice President
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