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                                                                  Exhibit 10.5.1

                        AMENDMENT NO. 1 TO AMENDED AND
                        ------------------------------
                        RESTATED REGISTRATION AGREEMENT
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          THIS AMENDMENT NO. 1 TO AMENDED AND RESTATED REGISTRATION AGREEMENT
(this "Amendment") is made and entered into as of June 30, 2000, by and
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among ChipPAC, Inc., a California corporation (the "Company"), Sapphire
                                                    -------
Worldwide Investments, Inc., a British Virgin Islands corporation ("Sapphire")
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and each of the other persons and entities listed on the signature pages hereto,
which persons and entities are, effective as of the date hereof, holders of not
less than a majority of the Company's Registrable Securities (as defined in the
Original Agreement described in this Amendment).  This Amendment amends that
certain Amended and Restated Registration Agreement dated as of August 5, 1999,
by and among the Company and each of the other shareholders of the Company
listed therein (the "Original Agreement").  Unless otherwise provided in this
                     ------------------
Agreement, capitalized terms used herein shall have the meanings set forth in
the Original Agreement.

          WHEREAS, the Company, Sapphire, Intersil Corporation and ChipPAC
Limited, the Company's wholly-owned indirect subsidiary, are parties to that
certain Stock Purchase Agreement dated as of June 30, 2000 (the "Purchase
                                                                 --------
Agreement"); and
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          WHEREAS, the execution and delivery of this Agreement is a condition
to the closing of the transactions contemplated by the Purchase Agreement.

          NOW, THEREFORE, in consideration of the premises and mutual covenants
herein contained, and other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged by the parties, and intending to be
legally bound hereby, the parties hereby agree as follows:

          1.  The second sentence of the first introductory paragraph of the
Original Agreement is hereby amended and restated in its entirety to read as
follows:

          The Hyundai Shareholders, the Bain Shareholders, the SXI Shareholders,
Intel, CSFB, Sankaty and Sapphire are collectively referred to herein as the
"Shareholders," and each as a "Shareholder."
 ------------                  -----------

          2.  Section 9 of the Original Agreement is hereby amended by adding
the following definitions:

          "Class C Preferred" means the Company's Class C Preferred Stock, par
           -----------------
value $.01 per share.

          "Sapphire Registrable Securities" means (i) any shares of Common Stock
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issued upon conversion of the Class C Preferred issued pursuant to the Purchase
Agreement, (ii) any equity securities issued or issuable directly or indirectly
with respect to the securities referred to in clause (i) by way of stock
dividend or stock split or in connection with a combination of shares,
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recapitalization, merger, consolidation or other reorganization, including a
recapitalization or exchange and (iii) any other shares of Common Stock held by
Persons holding securities described in clause (i) or (ii) above; provided that
in the event that pursuant to such recapitalization or exchange, Non-
Participating Securities are issued, such Non-Participating Securities will not
be Registrable Securities.  Notwithstanding anything in this Agreement to the
contrary, shares of Common Stock or other equity securities of the Company that
would otherwise constitute Sapphire Registrable Securities shall not be
considered Sapphire Registrable Securities (and thus, not Registrable
Securities) if the holder thereof can sell, in any three (3) month period, all
of such holder's shares or securities, as applicable, without registration
pursuant to Rule 144 under the Securities Act.  As to any particular shares
constituting Sapphire Registrable Securities, such shares will cease to be
Sapphire Registrable Securities when they have been (x) effectively registered
under the Securities Act and disposed of in accordance with the registration
statement covering them or (y) sold to the public through a broker, dealer or
market maker pursuant to Rule 144 (or by similar provision then in force) under
the Securities Act.

          3.  The definition of "Registrable Securities" set forth in Section 9
of the Original Agreement is hereby amended and restated in its entirety to read
as follows:

          "Registrable Securities" means collectively the Hyundai Registrable
           ----------------------
Securities, the Intel Registrable Securities, the Bain Registrable Securities,
the SXI Registrable Securities, the Financing Source Registrable Securities and
the Sapphire Registrable Securities.  For purposes of this Agreement, a Person
will be deemed to be a holder of Registrable Securities whenever such Person has
the right to acquire such Registrable Securities (upon conversion or exercise in
connection with a transfer of securities or otherwise, but disregarding any
restrictions or limitations upon the exercise of such right), whether or not
such acquisition has actually been effected.

          4.  Effectiveness. From and after the date of this Agreement, the
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holders of Sapphire Registrable Securities shall be a party to the Original
Agreement, as amended hereby, and shall have all of the rights and be subject to
all of the duties as a holder of Sapphire Registrable Securities. Except as
otherwise set forth in this Amendment, the terms of the Original Agreement shall
remain in full force and effect and shall remain unchanged.

          5.  Holdback Agreement. In addition to the holdback agreement set
              ------------------
forth in the Original Agreement, each holder of Sapphire Registrable Securities
agrees not to effect any sale or distribution (including sales pursuant to Rule
144) of equity securities of the Company, or any securities, options or rights
convertible into or exchangeable or exercisable for such securities, during the
seven days prior to and the 365-day period beginning on the effective date of
the Company's Initial Public Offering (the "Sapphire Holdback Period"); provided
                                            ------------------------
that upon any sale or distribution (including sales pursuant to Rule 144) of
Registrable Securities by any Bain Shareholder or any SXI Shareholder subsequent
to the effective date of the Company's Initial Public Offering and prior to the
expiration of the Sapphire Holdback Period, the additional restrictions
contained in this Section 5 shall immediately terminate with respect to a number
of Sapphire Registrable Securities equal to the product of (A) the greater of
(i) the quotient determined by dividing the number of Registrable Securities
sold or distributed by the transferring Bain Shareholder(s) in such sale, if
any, by the aggregate number of Registrable Securities (prior to giving effect
to such sale or distribution) owned by all Bain Shareholders or (ii) the
quotient determined by

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dividing the number of Registrable Securities sold or distributed by any
transferring SXI Shareholder(s) in such sale, if any, by the aggregate number of
Registrable Securities (prior to giving effect to such sale or distribution)
owned by all SXI Shareholders and (B) the aggregate number of Sapphire
Registrable Securities as of the time of such sale or distribution.
Notwithstanding the foregoing, each holder of Sapphire Registrable Securities
shall continue to be bound by the holdback agreement set forth in the Original
Agreement.

          6.  Integration. Any reference in the Original Agreement to the term
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"Agreement" is deemed to refer to both the Original Agreement as well as the
Original Agreement, as amended by this Amendment.

          7.  Miscellaneous.
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          (a) Amendments and Waivers. Except as otherwise provided herein, the
              ----------------------
provisions of this Amendment may be amended or waived only upon the prior
written consent of the Company and holders of a majority of the Registrable
Securities; but if such amendment or waiver would treat a holder or group of
holders of Registrable Securities in a manner different from any other holders
of Registrable Securities, then such amendment or waiver will require the
consent of such holder or the holders of a majority of the Registrable
Securities of such group adversely treated.

          (b) Successors and Assigns. This Amendment will be binding upon and
              ----------------------
inure to the benefit of and be enforceable by the parties hereto and their
respective successors and assigns. In addition, and whether or not any express
assignment has been made, the provisions of this Amendment that are for the
benefit of the holders of Registrable Securities (or any portion thereof) as
such will be for the benefit of and enforceable by any subsequent holder of any
Registrable Securities (or of such portion thereof), subject to the provisions
respecting the minimum numbers or percentages of shares of Registrable
Securities (or of such portion thereof) required in order to be entitled to
certain rights, or take certain actions, contained herein.

          (c) Severability. Whenever possible, each provision of this Amendment
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will be interpreted in such manner as to be effective and valid under applicable
law, but if any provision of this Amendment is held to be invalid, illegal or
unenforceable in any respect under any applicable law or rule in any
jurisdiction, such invalidity, illegality or unenforceability will not affect
any other provision or the effectiveness or validity of any provision in any
other jurisdiction, and this Amendment will be reformed, construed and enforced
in such jurisdiction as if such invalid, illegal or unenforceable provision had
never been contained herein.

          (d) Counterparts. This Amendment may be executed simultaneously in
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two or more counterparts, any one of which need not contain the signatures of
more than one party, but all such counterparts taken together will constitute
one and the same agreement.

          (e) Descriptive Headings. The descriptive headings of this Amendment
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are inserted for convenience only and do not constitute a part of this
Amendment.

          (f) Governing Law. All issues concerning the enforceability, validity
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and binding effect of this Amendment will be governed by and construed in
accordance with the laws of the State

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of California, without giving effect to any choice of law or conflict of law
provision or rule (whether of the State of California or any other jurisdiction)
that would cause the application of the law of any jurisdiction other than the
State of California.

          (g)  Notices. All notices, demands or other communications to be given
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or delivered under or by reason of the provisions of this Amendment will be in
writing and will be deemed to have been given when personally delivered or
received by certified mail, return receipt requested, or sent by guaranteed
overnight courier service. Such notices, demands and other communications shall
be sent to the addresses listed in the Original Agreement, the addresses
indicated below or, if no address is so indicated for any particular
Shareholder, at the address listed in the Company's records:

          If to Sapphire:
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          Sapphire Worldwide Investments, Inc.
          c/o Intersil Corporation
          7585 Irvine Center Drive, Suite 100
          Irvine, California 92618
          Attention: Gregory L. Williams
          Facsimile No.: (949) 341-7053

          With a copy to:
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          Intersil Corporation
          7585 Irvine Center Drive, Suite 100
          Irvine, California 92618
          Attention: Steven M. Moran, Esq.
          Facsimile No.: (949) 341-7053

or to such other address or to the attention of such other person as the
recipient party has specified by prior written notice to the sending party.

                                 *  *  *  *  *

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          IN WITNESS WHEREOF, the parties have executed this Amendment No. 1 to
Amended and Restated Registration Agreement on the day and year first above
written.

                              CHIPPAC, INC.

                              By: /s/ Sharon St. Clair-Douglas
                                 _________________________________

                              Its:  Power of Attorney
                                  ________________________________

                              SAPPHIRE:

                              SAPPHIRE WORLDWIDE INVESTMENTS, INC.

                              By: /s/ Howard Rothman
                                 _________________________________

                              Its:  Assistant Secretary
                                  ________________________________

                              THE BAIN SHAREHOLDERS:

                              BAIN CAPITAL FUND VI, L.P.

                              By:  Bain Capital Partners VI, L.P.
                              Its: General Partner

                              By:  Bain Capital Investors, Inc.
                              Its: General Partner

                              By:  /s/ Edward Conrad
                                 _________________________________
                                   A Managing Director

                              BCIP ASSOCIATES II

                              By:  /s/ Edward Conrad
                                 _________________________________
                                   A General Partner
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                              BCIP ASSOCIATES II-B

                              By: /s/ Edward Conrad
                                 _________________________________
                                   A General Partner

                              BCIP ASSOCIATES II-C

                              By: /s/ Edward Conrad
                                 _________________________________
                                   A General Partner

                              BCIP TRUST ASSOCIATES II

                              By:  Bain Capital, Inc.
                              Its: General Partner

                              By: /s/ Edward Conrad
                                 _________________________________
                                   A Managing Director

                              BCIP TRUST ASSOCIATES II-B

                              By:  Bain Capital, Inc.
                              Its: General Partner

                              By: /s/ Edward Conrad
                                 _________________________________
                                   A Managing Director

                              PEP INVESTMENTS PTY., LTD.

                              By: /s/ Edward Conrad
                                 _________________________________

                              Its: General Partner
                                  ________________________________

                              RANDOLPH STREET PARTNERS II

                              By: /s/ Gary Holihan
                                 _________________________________
                                   A General Partner
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                              SXI GROUP LLC

                              By: /s/ Paul C. Schorr, IV
                                 _________________________________

                              Its:   Member
                                  ________________________________