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                                                                  EXHIBIT 4.2(c)

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                         ADVANCED MICRO DEVICES, INC.

                                    ISSUER

                       11% Senior Secured Notes due 2003


                       ---------------------------------

                         SECOND SUPPLEMENTAL INDENTURE

                           Dated as of April 8, 1999

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                    United States Trust Company of New York

                                    TRUSTEE

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                         SECOND SUPPLEMENTAL INDENTURE
                         -----------------------------

          This SECOND SUPPLEMENTAL INDENTURE (this "Second Supplemental
Indenture"), dated as of April 8, 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 "Original 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. Pursuant to the provisions of the Indenture and with the consent of
the holders of at least a majority in principal amount of the outstanding Notes,
the Company and the Trustee have amended, modified and supplemented the Original
Indenture by that certain First Supplemental Indenture dated as of January 13,
1999 (the Original Indenture, as amended by the First Supplemental Indenture,
being the "Indenture"). Capitalized terms used herein without definition shall
have the same meanings herein as set forth in the Indenture.

          C. Under the Indenture, unless certain financial tests can be met, the
Company is only permitted to make Restricted Investments up to specified amounts
and/or for certain purposes, and may not reallocate or adjusts the amounts of
such permitted exceptions. One such permitted exception (which has not been
utilized to date) permits the Company to make Investments of up to $50 million,
but restricts those Investments to the FASL Unrestricted Subsidiary.

          D. The Company expects it may need to make certain Restricted
Investments outside of the existing permitted exceptions and, in particular, to
use the $50 million currently allocated to the FASL Unrestricted Subsidiary for
other Restricted Investments (including, without limitation, Investments in the
Dresden, Germany Unrestricted Subsidiary).

          E. The Company and the Trustee now desire to amend, modify and
supplement the Indenture, in the respects hereinafter set forth, to specifically
permit, absent an Event of Default, additional Investments of up to $70 million,
without additional restrictions and to reallocate $50 million (which is
currently restricted to investment in the FASL Unrestricted Subsidiary) to
general investment purposes, making a total of $120 million available for such
general investments.

          F. The Indenture further provides that the Company may, at its option,
apply the Net Proceeds from any Asset Sale to certain uses, including, without
limitation, the permanent reduction of amounts outstanding under the New Credit
Agreement (and to correspondingly reduce commitments with respect thereto).

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          G. The Company and the Trustee now desire to amend, modify and
supplement the Indenture, the respects hereinafter set forth, to provide that,
from and after the date of this Second Supplemental Indenture, the Company
shall, following receipt of the Net Proceeds from Asset Sales (including,
without limitation, Asset Sales of the capital stock or assets of the PLD
Subsidiary), apply the cash portion of such aggregate Net Proceeds to the
reduction of outstanding term loans made pursuant to the New Credit Agreement,
until such term loans shall have been reduced by at least $70 million in the
aggregate.

          H. 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 Second Supplemental Indenture.

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

          Section 1.  Incorporation of the Indenture. Except as specifically
                      ------------------------------
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 1.01
                      ------------------------------------------
of the Indenture is hereby amended by adding the following definition of "Second
Supplemental Indenture":

          "'Second Supplemental Indenture' means that certain Second
     Supplemental Indenture, dated as of April 8, 1999, by and between the
     Company and the Trustee."

          Section 3.  Amendment to Section 4.07 of the Indenture. Section 4.07
                      ------------------------------------------
of the Indenture is hereby amended by deleting the paragraph immediately
following subparagraph (c) in its entirety and inserting in lieu thereof the
following text:

          "Provided that no Event of Default shall have occurred and be
     continuing, the foregoing provisions will not prohibit (i) the payment of
     any dividend within 60 days after the date of declaration thereof, if at
     said date of declaration such payment would have complied with the
     provisions of this Indenture; (ii) the redemption, repurchase, retirement
     or other acquisition of any Equity Interests of the Company in exchange
     for, or out of the proceeds of, the substantially concurrent sale (other
     than to a Subsidiary of the Company) of other Equity Interests of the
     Company (other than any Disqualified Stock) or the substantially concurrent
     conversion of such Equity Interests for other Equity Interests of the
     Company (other than Disqualified Stock); provided that the amount of any
     such net cash proceeds that are utilized for any such redemption,
     repurchase, retirement or other acquisition shall be excluded from clause
     (c)(ii) of the preceding paragraph; (iii) the making of any principal
     payment on, or the purchase, redemption, defeasance or other acquisition or
     retirement for value of any

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     subordinated Indebtedness with the net cash proceeds from an incurrence of
     Permitted Refinancing Indebtedness or the substantially concurrent sale
     (other than to a Subsidiary of the Company) of Equity Interests of the
     Company (other than Disqualified Stock) or the substantially concurrent
     conversion of such Indebtedness into Equity Interests of the Company (other
     than Disqualified Stock); provided that the amount of any such net cash
     proceeds that are utilized for any such redemption, repurchase, retirement
     or other acquisition shall be excluded from clause (c)(ii) of the preceding
     paragraph; (iv) the making of a Guarantee (but not the payment of such
     Guarantee) by the Company of up to $175.0 million of the FASL Unrestricted
     Subsidiary's Indebtedness; (v) any payments by the Company required
     pursuant to the CIBC Guarantee; (vi) Restricted Payments in an aggregate
     amount not to exceed $10.0 million; and (vii) Investments by the Company of
     up to $120.0 million."

          Section 4.  Amendment to Section 4.10(a) of the Indenture. Section
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4.10(a) of the Indenture is hereby amended by deleting the second paragraph of
subparagraph (a) in its entirety and inserting in lieu thereof the following
text:

          "Within 24 months after the receipt of any Net Proceeds from an Asset
     Sale, the Company may apply, or may cause the applicable Restricted
     Subsidiary to apply, such Net Proceeds to (i) the acquisition by the
     Company of all of the Capital Stock of any Person in the same or a
     substantially similar line of business as that conducted by the Company or
     any of its Subsidiaries as of the Issue Date, (ii) the making of a capital
     expenditure, (iii) the acquisition of other long-term Tangible Assets, (iv)
     the permanent reduction of amounts outstanding under the New Credit
     Agreement (and to correspondingly reduce commitments with respect thereto)
     and (v) the making of a Restricted Strategic Investment which is a
     Permitted Investment. Notwithstanding anything to the contrary in this
     Indenture, from and after the date of the Second Supplemental Indenture,
     within 30 Business Days after the receipt by the Company of Net Proceeds
     from Asset Sales (including without limitation, Asset Sales of all or any
     portion of the assets or Equity Interests in the PLD Subsidiary), the
     Company shall apply the cash portion of such aggregate Net Proceeds to the
     reduction of the amounts outstanding under the term loans made pursuant to
     the New Credit Agreement, until the amounts outstanding under such term
     loans shall have been reduced by an aggregate amount of at least $70
     million. Pending the final application of any such Net Proceeds, the
     Company shall hold such Net Proceeds in the form of cash or Cash
     Equivalents. Any Net Proceeds from Asset Sales that are not applied or
     invested as provided in the first or second sentences of this paragraph
     will be deemed to constitute "Excess Proceeds.""

          Section 5.  Counterparts. This Second Supplemental Indenture may be
                      ------------
executed in several counterparts, each of which shall be deemed an original but
shall constitute one and the same instrument.

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          Section 6.  Effectiveness. This Second Supplemental Indenture shall
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become effective as of the date first written above.

          Section 7.  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 Second
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.

                                 /s/Francis P. Barton
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                        By: Francis P. Barton
                        Title: Senior Vice President and Chief Financial Officer


                        UNITED STATES TRUST COMPANY OF NEW YORK, as Trustee

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