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                             CONFIDENTIAL TREATMENT

                                                                  EXHIBIT 10.5.2

                                1995 AMENDMENT TO
                    TECHNOLOGY TRANSFER AND FOUNDRY AGREEMENT
                                       AND
                            CO-DEVELOPMENT AGREEMENT

                  This 1995 Amendment to Technology Transfer and Foundry
Agreement and Co-Development Agreement ("Agreement") is entered into as of
August 16, 1995 between SEEQ Technology Incorporated ("SEEQ"), a Delaware
corporation having a place of business at Fremont, California, and Hualon
Microelectronics Corporation, a Taiwanese corporation ("HMC") that has a place
of business at Hsinchu, Taiwan. This Agreement shall become effective on the
date (the "Effective Date") of execution of the Settlement Agreement, Release
and Tolling Agreement dated the date hereof entered into between SEEQ and HMC
("Settlement Agreement").

                                    RECITALS

         1.10 SEEQ and HMC entered into a Technology Transfer and Foundry
Agreement dated as of July 16, 1990 (the "1990 Foundry Agreement") pursuant to
which HMC served as a foundry for SEEQ to manufacture certain logic and other
ICs.

         1.11 The Parties entered into a Co-Development Agreement dated February
24, 1992 (Co-Development Agreement.")

[*] INDICATES THAT MATERIAL HAS BEEN OMITTED AND CONFIDENTIAL TREATMENT HAS BEEN
REQUESTED THEREFOR. ALL SUCH OMITTED MATERIAL HAS BEEN FILED SEPARATELY WITH THE
COMMISSION PURSUANT TO RULE 24b-2.



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         1.12 SEEQ and HMC have entered into the Settlement Agreement pursuant
to which SEEQ and HMC have agreed to settle certain disputes under the 1990
Foundry Agreement and the Co-Development Agreement.

         1.13 In connection with the implementation of the Settlement Agreement,
the parties desire to amend the terms and conditions of the 1990 Foundry
Agreement and the Co-Development Agreement with respect to [*] Products and [*]
Processes;

         Accordingly, SEEQ and HMC agree to the following terms and conditions:

         1.       INTRODUCTION

                  1.1 This Agreement amends and modifies the 1990 Foundry
Agreement and the Co-Development Agreement. Except as amended hereby, each of
said agreements shall each remain in full force and effect. In the event of any
inconsistency or other conflict between this Agreement and either or both of the
1990 Foundry Agreement or the Co-Development Agreement, the terms of this
Agreement shall prevail, and the other agreement is deemed amended by this
Agreement.

                  1.2 Except as otherwise defined herein, capitalized terms
shall have the meanings given to them in the 1990 Foundry Agreement.

                  1.3 [*] Products means SEEQ's [*], [*] and [*] products.

[*] INDICATES THAT MATERIAL HAS BEEN OMITTED AND CONFIDENTIAL TREATMENT HAS BEEN
REQUESTED THEREFOR. ALL SUCH OMITTED MATERIAL HAS BEEN FILED SEPARATELY WITH THE
COMMISSION PURSUANT TO RULE 24b-2.


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                  1.4 [*] Process means the [*] CMOS 1.2-micron Process that was
delivered by SEEQ to HMC and subsequently modified and developed by HMC and that
is now known as [*]. 

2. FOUNDRY SERVICES

                  2.1 Minimum Wafer Foundering. Upon the terms and conditions
set forth herein, at SEEQ's request, HMC shall manufacture Articles of [*]
Products for delivery to SEEQ. HMC may also, but shall not be obligated to,
manufacture wafers for Products Developed by SEEQ in addition to the [*]
Products, as determined by the PARTIES. After execution of the Settlement
Agreement, HMC shall, upon request from SEEQ, based on a four (4) week month,
make wafer starts available to SEEQ at a minimum of (a) [*] 125-millimeter
wafers (or equivalents in other size wafers) started during the period from the
Effective Date through August 31, 1995, (b) [*] 125-millimeter wafer starts (or
equivalents in other size wafers) started per month (at the rate of
approximately [*] wafers per week) during the period from September 1, 1995
until the earlier of (i) the end of the term of the 1990 Foundry Agreement, or
(ii) the date in which the [*] Products have been qualified by SEEQ for
manufacture on the [*] Stepper, and (c) [*] 125-millimeter wafer starts (or
equivalents in other size wafers) started per month (at the rate of
approximately [*] wafers per week) during the period following

[*] INDICATES THAT MATERIAL HAS BEEN OMITTED AND CONFIDENTIAL TREATMENT HAS BEEN
REQUESTED THEREFOR. ALL SUCH OMITTED MATERIAL HAS BEEN FILED SEPARATELY WITH THE
COMMISSION PURSUANT TO RULE 24b-2.

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the date on which the [*] Products have been qualified by SEEQ for manufacture
on the [*] Stepper.

                  2.2 Pricing. The initial prices per wafer of [*] Products
foundered by HMC shall be as set forth in Appendix B to the 1990 Foundry
Agreement, which appendix is modified to read as set forth in Appendix B hereto.

         3.       ROYALTIES

                  Neither HMC nor SEEQ shall be required to pay any royalty to
the other with respect to the sale of any of the [*] Products, including any
HMC-Improved or SEEQ-Improved version(s) of each such product, as the case may
be.

         4.       NOTICES

                  All notices given under the 1990 Foundry Agreement
shall be in writing and shall be sufficient if delivered in
person or mailed, postage prepaid, registered or certified mail,
return receipt requested, or transmission by telecopier with
confirmation of receipt, to the PARTIES at the following
addresses:
SEEQ:                               SEEQ Technology Incorporated
                                    4200 Bayside Parkway
                                    Fremont, California 94538
                                    Attn: President and Chief Executive Officer
                                    Telecopier: (510) 657-2837

With a copy to:            Brobeck, Phleger & Harrison
                                    One Market

[*] INDICATES THAT MATERIAL HAS BEEN OMITTED AND CONFIDENTIAL TREATMENT HAS BEEN
REQUESTED THEREFOR. ALL SUCH OMITTED MATERIAL HAS BEEN FILED SEPARATELY WITH THE
COMMISSION PURSUANT TO RULE 24b-2.


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                                    San Francisco, CA 94105
                                    Attn: Scott D. Lester, Esq.
                                    Telecopier: (415) 442-1010

HMC:                                Hualon Microelectronics Corporation
                                    6th Floor, Kua Hua Life Insurance Building
                                    42 Chung Shan North Road, Station 2
                                    Taipei, Taiwan
                                    Attn: President and CEO
                                    Telecopier: 886-2-531-3241

With a copy to:                     Hanson, Bridgett, Marcus, Vlahos & Rudy
                                    333 Market Street, Suite 2300
                                    San Francisco, CA 94105
                                    Attn: William J. Bush, Esq.
                                    Telecopier: (415) 541-9366

         5.       YIELD IMPROVEMENT

                  HMC and SEEQ agree that both Parties shall work together
immediately following the Effective Date of this Agreement (a) to enable HMC to
return probe yields to the levels achieved during 1994 (i.e., in excess of [*]
die per wafer for the [*]) and (b) to thereafter continue to work together to
further improve yields in the manufacture of the SEEQ Products.

         6.       PAYMENTS FOR FOUNDRIED PRODUCTS

                  SEEQ shall pay for foundried Products, and shall pay for Mask
Generation Costs, all in accordance with Appendix B. SEEQ shall pay HMC all
amounts due under this Agreement within thirty (30) days after the receipt by
SEEQ of an invoice for such charges. HMC reserves the right to modify such
payment terms if any amount payable is sixty (60) days past due (unless such

[*] INDICATES THAT MATERIAL HAS BEEN OMITTED AND CONFIDENTIAL TREATMENT HAS BEEN
REQUESTED THEREFOR. ALL SUCH OMITTED MATERIAL HAS BEEN FILED SEPARATELY WITH THE
COMMISSION PURSUANT TO RULE 24b-2.
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amount is being contested in good faith), or if SEEQ has become insolvent or is
not able to pay its debts as they become due.

         7.       MINIMUM WAFER PURCHASE REQUIREMENTS

                  The Parties acknowledge that Paragraph 7.2 of the 1990 Foundry
Agreement which deals with minimum wafer purchase requirements for SEEQ shall no
longer be applicable.

         IN WITNESS WHEREOF, authorized officers or representatives of the
Parties have executed this Agreement on the dates entered below.

SEEQ TECHNOLOGY INCORPORATED              HUALON MICROELECTRONICS CORPORATION

By ___________________________            By ___________________________
     ____________________                      ____________________     
     ____________________                      ____________________     
                                            

Date _______________________              Date _______________________


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                                   APPENDIX B

                         [*] FOUNDRY DETAIL AND PRICING

1.       EVALUATION, QUALIFICATION, RISK AND PRICING

         1.1      Initial Pricing Terms.  The initial prices for the [*],
                  the [*] and the new [*] design shall be as set forth
                  below:

                  1.1.1    [*] Initial Pricing.  Initial pricing for the
                           [*] shall be [*] per wafer.

                  1.1.2    [*] Initial Pricing. Initial pricing for the [*]
                           shall be (i) [*] per sorted die (or [*] per die if
                           sorted at SEEQ) for all die invoiced prior to
                           December 31, 1995, and (ii) [*] per sorted die (or
                           [*] per die if sorted at SEEQ) for all die invoiced
                           after January 1, 1996.

                  1.1.3    [*] Initial Pricing. Initial pricing for SEEQ's new
                           [*] design shall be based on actual sort yields, when
                           available, and negotiated against an effective wafer
                           price target of [*] per wafer.

         1.2      Yield Improvements; Future Price Reductions. The PARTIES agree
                  that they will work diligently and with their respective best
                  efforts to achieve yield improvements in the manufacture of
                  the [*] Products hereunder. HMC agrees that, in consideration
                  for SEEQ's efforts in the attempt to improve such yields, HMC
                  will negotiate in good faith with SEEQ to reduce the prices
                  set forth above (i) for the [*] Product manufactured hereunder
                  so that SEEQ may obtain a share of the benefits of yield
                  improvements in excess of [*] die per wafer, and (ii) for the
                  [*] and [*] Products, the Parties shall share the benefits
                  over the base line yields to be agreed upon once mass
                  production of such Products commences.

         1.3      [*] Stepper. HMC shall take all required actions to bring the
                  [*] Stepper on-line as soon as possible following the
                  Effective Date to enable HMC to

[*] INDICATES THAT MATERIAL HAS BEEN OMITTED AND CONFIDENTIAL TREATMENT HAS BEEN
REQUESTED THEREFOR. ALL SUCH OMITTED MATERIAL HAS BEEN FILED SEPARATELY WITH THE
COMMISSION PURSUANT TO RULE 24b-2.

 

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                  manufacture [*] Products utilizing the [*] Stepper and to
                  enable HMC to achieve increased manufacturing capacity for the
                  [*] Products to be purchased by SEEQ. SEEQ and HMC agree to
                  develop a program immediately following the Effective Date to
                  accomplish this capacity increase. SEEQ agrees to take all
                  necessary actions to assist HMC to accomplish this capacity
                  increase.

         1.4      HMC Engineering Services.

                  1.4.1    HMC agrees to provide the engineering services to
                           build the mask sets and process engineering lots
                           required to update the [*] mask set and to bring the
                           [*] Stepper on-line to achieve increased capacity.
                           The new mask sets are to be used for the manufacture
                           of products for both SEEQ and HMC.

                  1.4.2    HMC agrees to provide the engineering services to
                           build the mask sets and process engineering lots
                           required to bring up the latest revision of the [*]
                           in HMC's manufacturing facility. The new mask sets
                           are to be used for the manufacture of products for
                           both SEEQ and HMC.

                  1.4.3    HMC agrees to provide the engineering services to
                           build the mask sets and process engineering lots
                           required to bring up the new [*] design in HMC's
                           manufacturing facility. The new mask sets are to be
                           used for the manufacture of products for both SEEQ
                           and HMC.

         1.5      Database Update. SEEQ shall update the [*] and [*] databases
                  for use by HMC in accordance with its contractual rights. Such
                  updates shall incorporate any present or future design
                  improvements completed by SEEQ during the term of this
                  Agreement and shall accommodate the use of the [*] Stepper, if
                  technically feasible.

         1.6      The [*].  SEEQ shall also provide to HMC the initial
                  database of the [*] Product, once it has been
                  developed, and shall provide database updates for the
                  [*] Product during the term of this Agreement.  HMC

[*] INDICATES THAT MATERIAL HAS BEEN OMITTED AND CONFIDENTIAL TREATMENT HAS BEEN
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                  shall not sell the [*] Product outside of the Permitted
                  Territories prior to the end of the term of the 1990 Foundry
                  Agreement, provided, however, that prior to the end of such
                  term HMC may sell the [*] Product to its sakes agent or
                  representative who may not be located within the Permitted
                  Territories if such sale is solely for resale in the Permitted
                  Territories.

         1.7      NRE Payments.  SEEQ shall pay Non-recurring Engineering
                  ("NRE") charges as follows:

                  1.7.1    SEEQ shall pay to HMC all NRE charges incurred to
                           establish [*] manufacturing in HMC's Facility, and
                           shall pay such charges within thirty (30) days after
                           receipt of an invoice therefor, as follows:

                           (a)      SEEQ shall pay to HMC [*] upon delivery to
                                    HMC of a completed mask set by the mask
                                    vendor;

                           (b)      SEEQ shall pay to HMC [*] upon delivery by
                                    HMC to SEEQ of eight (8) or more wafers from
                                    the first engineering lot under this
                                    Agreement;

                           (c)      SEEQ shall pay to HMC [*] upon delivery by
                                    HMC to SEEQ of eight (8) or more wafers from
                                    the second engineering lot under this
                                    Agreement.

                  1.7.2    SEEQ shall pay to HMC all NRE charges incurred to
                           transfer the [*] product for manufacturing in HMC's
                           Facility, and shall pay such charges within thirty
                           (30) days after receipt of an invoice therefor, as
                           follows:

                           (a)      SEEQ shall pay to HMC [*] upon delivery to
                                    HMC of a completed mask set by the mask
                                    vendor;

                           (b)      SEEQ shall pay to HMC [*] upon delivery by
                                    HMC to SEEQ of eight (8) or more wafers from
                                    the first engineering lot

[*] INDICATES THAT MATERIAL HAS BEEN OMITTED AND CONFIDENTIAL TREATMENT HAS BEEN
REQUESTED THEREFOR. ALL SUCH OMITTED MATERIAL HAS BEEN FILED SEPARATELY WITH THE
COMMISSION PURSUANT TO RULE 24b-2.


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                                    under this Agreement;

                           (c)      SEEQ shall pay to HMC [*] upon delivery by
                                    HMC to SEEQ of eight (8) or more wafers from
                                    the second engineering lot under this
                                    Agreement.

                  1.7.3    SEEQ shall pay to HMC all NRE charges incurred to
                           transfer and for start-up of the [*] product for
                           manufacturing in HMC's Facility, and shall pay such
                           charges within thirty (30) days after receipt of an
                           invoice therefor, as follows:

                           (a)      SEEQ shall pay to HMC [*] upon delivery to
                                    HMC of a completed mask set by the mask
                                    vendor;

                           (b)      SEEQ shall pay to HMC [*] upon delivery by
                                    HMC to SEEQ of eight (8) or more wafers from
                                    the first engineering lot under this
                                    Agreement;

                           (c)      SEEQ shall pay to HMC [*] upon delivery by
                                    HMC to SEEQ of eight (8) or more wafers from
                                    the second engineering lot under this
                                    Agreement.

                  1.7.4    It is the intent of SEEQ and HMC that all NRE work to
                           be performed under this Agreement will be completed
                           by December 31, 1995, and that all NRE charges to be
                           paid by SEEQ under this Agreement will be paid by
                           December 31, 1995.

         1.8      Other Matters.

                  1.8.1    HMC acknowledges that SEEQ expects that the [*]
                           Process will be rapidly brought into control and will
                           yield consistently at wafer sort. HMC agrees to use
                           its best efforts, and SEEQ agrees to cooperate with
                           HMC, to ensure this is achieved.

                  1.8.2    Wafer acceptance is to be subject to normal
                           e-test, visual and workmanship criteria.  The

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                           PARTIES shall cooperate to determine these matters.

                  1.8.3    Scrap criteria and RMA policy on misprocessed wafers
                           must be competitive. The PARTIES shall cooperate to
                           determine these matters.

         1.9      E-Sort.

                  1.9.1    E-sort will be done either at SEEQ's facility in
                           Fremont, or at HMC's facility in Taiwan, and each
                           PARTY will have auditing rights for the E-sort
                           facility of the other PARTY during normal working
                           hours and with reasonable notice. Proposed changes of
                           software or hardware will follow the same procedure
                           as fab process changes.

                  1.9.2    All E-sort documentation will be maintained for 24
                           months. Each week, the E-sort area will provide the
                           following information to both PARTIES:

                           -        wafers received by lot number, product and
                                    date received

                           -        wafers E-sorted by lot number and date
                                    E-sorted

                           -        die yield by lot number and product

                           -        wafers waiting to be E-sorted by lot number
                                    and product.

                  1.9.3    At HMC's option, E-sort can be transferred to a
                           SEEQ-qualified HMC facility. Any change in die price
                           for HMC's E-sort will be determined by the PARTIES.