As filed with the Securities and Exchange Commission on August 23, 2004
                                                      Registration No. 333-38033

     =====================================================================

                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                         POST-EFFECTIVE AMENDMENT NO. 6

                                   on Form S-8
                                   to Form S-4

                          REGISTRATION STATEMENT UNDER
                           THE SECURITIES ACT OF 1933

                       NATIONAL SEMICONDUCTOR CORPORATION
             (Exact name of registrant as specified in its charter)

         DELAWARE                                          95-2095071
         --------                                          ----------
(State or other jurisdiction of                          (I.R.S. Employer
incorporation or organization)                            Identification Number)

                            2900 Semiconductor Drive
                                 P.O. Box 58090
                       Santa Clara, California 95052-8090
                    (Address of principal executive offices)
        Registrant's telephone number including area code: (408) 721-5000
                 ----------------------------------------------

                   Cyrix Corporation 1988 Incentive Stock Plan
                            (Full Title of the Plan)

                             JOHN M. CLARK III, Esq.
                     Senior Vice President, General Counsel
                                  and Secretary
                       NATIONAL SEMICONDUCTOR CORPORATION
                      2900 Semiconductor Drive, P.O. 58090
                           Santa Clara, CA 95052-8090
                                 (408) 721-5000

           (Name, address and telephone number, of agent for service)




                                     PART I
                                EXPLANATORY NOTE

DEREGISTRATION OF SHARES

     Pursuant to Post Effective No. 1 on Form S-8 to Registration  Statement No.
333-38033 on Form S-4 (the  "Registration  Statement"),  National  Semiconductor
Corporation,  a Delaware  corporation  (the  "Company"),  registered  5,493,012*
shares of its Common Stock,  $0.50 par value per share ("Common Stock") issuable
under the Cyrix  Corporation  1988 Incentive  Stock Plan (the "Plan").  Upon the
merger of Nova  Acquisition  Corp.,  a Delaware  corporation  and a wholly owned
subsidiary  of the  Company,  into Cyrix  Corporation,  a Delaware  corporation,
outstanding options issued pursuant to the Plan became exercisable for shares of
Company  Common  Stock.  All  options  under the Plan have now  expired  and the
Company  hereby  removes  from  registration  under the  Registration  Statement
3,980,752 shares which remain unissued in connection with the Plan.



*All share numbers  adjusted to reflect the two-for-one  stock split paid in the
form of a 100% stock dividend in May 2004.



                                     PART II

Item 8.  Exhibits

24.1     Power of Attorney



                                   SIGNATURES

     Pursuant to the requirements of the Securities Act of 1933, as amended, the
Company  certifies that it has  reasonable  grounds to believe that it meets all
the  requirements for filing this  Post-Effective  Amendment to the Registration
Statement  on Form S-8 to Form S-4  (Registration  No.  333-38033)  and has duly
caused this Post-Effective  Amendment to the Registration Statement to be signed
on its behalf by the  undersigned,  thereunto  duly  authorized,  in the City of
Santa Clara, State of California on August 23, 2004.

                                          NATIONAL SEMICONDUCTOR CORPORATION

                                          By    BRIAN L. HALLA*
Brian L. Halla
                                          Chairman of the Board, and
                                          Chief Executive Officer

     Pursuant to the  requirements  of the  Securities  Act of 1933, as amended,
this Post-Effective Amendment to the Registration Statement on Form S-8 has been
signed below by the following persons in the capacities  indicated on August 23,
2004.

  BRIAN L. HALLA*                          Chairman of the Board, President,
  (Brian L.Halla)                          Chief Executive Officer and Director
                                           (Principal Executive Officer)

  LEWIS CHEW*                              Senior Vice President, Finance and
  (Lewis Chew)                             Chief Financial Officer
                                           (Principal Financial Officer)

  ROBERT E. DeBARR*                        Controller (Principal Accounting
  (Robert E. DeBarr)                       Officer)

  STEVEN R. APPLETON*                      Director
  (Steven R. Appleton)

  GARY P. ARNOLD*                          Director
  (Gary P. Arnold)

  RICHARD J. DANZIG*                       Director
  (Richard J. Danzig)

  ROBERT J. FRANKENBERG*                   Director
  (Robert J. Frankenberg)

  E. FLOYD KVAMME*                         Director
  (E. Floyd Kvamme)

  MODESTO A. MAIDIQUE*                     Director
  (Modesto A. Maidique)

  EDWARD R. McCRACKEN*                     Director
  (Edward R. McCracken)

*By:  __//S// JOHN M. CLARK III____
       John M. Clark III, Attorney in Fact




                       NATIONAL SEMICONDUCTOR CORPORATION

                                  EXHIBIT INDEX

24.1     Power of Attorney





                                                                    Exhibit 24.1

                                POWER OF ATTORNEY


KNOW ALL MEN BY THESE  PRESENTS,  that each of the  undersigned  persons  hereby
constitutes and appoints Brian L. Halla,  Lewis Chew, and John M. Clark III, and
each of them  singly,  his true and  lawful  attorney-in-fact  and in his  name,
place, and stead, and in any and all of his offices and capacities with National
Semiconductor   Corporation,   to  sign  the  Post-Effective  Amendment  to  the
Registration  Statement with which this Power of Attorney is filed,  and any and
all amendments to said Posst-Effective  Amendment to Registration Statement, and
generally  to do and  perform  all things and acts  necessary  or  advisable  in
connection  therewith,  and each of the undersigned hereby ratifies and confirms
all that each of said  attorneys-in-fact  may lawfully do or cause to be done by
virtue hereof.

     IN WITNESS  WHEREOF,  each of the  undersigned  has hereunto  executed this
Power of Attorney as of the date set forth opposite his signature.


                    SIGNATURE                               DATE



  //S// STEVEN R. APPLETON                                 July 14, 2004
  Steven R. Appleton


  //S// RICHARD J. DANZIG                                  July 14, 2004
  Richard J. Danzig


  //S// ROBERT J. FRANKENBERG                              July 14, 2004
  Robert J. Frankenberg


  //S// E. FLOYD KVAMME                                    July 14, 2004
  E. Floyd Kvamme


  //S// LEWIS CHEW                                         July 9, 2004
  Lewis Chew


  //S// ROBERT E. DeBARR                                   July 9, 2004
  Robert E. DeBarr