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                                                                   EXHIBIT 10.51

                    AMENDMENT TO JOINT DEVELOPMENT AGREEMENT

        This Amendment ("Amendment") to the parties' Joint Development Agreement
("Agreement") dated December 14, 2001, is entered into and effective as of this
18th day of January 2003, by and between ESS Technology Inc., ("ESS"), a
California corporation having a registered office at 48401 Fremont Blvd.,
Fremont, CA 94538, and *** ("Counterparty*"), a corporation organized under the
laws of ***, having a principal place of business at ***.

        WHEREAS, the parties have entered into the Joint Development Agreement;
and

        WHEREAS; the parties desire to amend and clarify the terms of the Joint
Development Agreement as set forth herein.

        NOW, THEREFORE, in consideration of the mutual promises contained herein
and for good and valuable consideration, the receipt and sufficiency of which is
hereby acknowledged, the parties hereby agree as follows:

        1. Section 1 "Definitions" shall be amended to include the following
defined terms:

        "Assembly Facility" shall mean ***, or such other assembly, packaging,
        and testing facility as has been agreed to by the parties.

        "Foundry" shall mean *** or such other foundry as has been agreed to by
        the parties.

        2. Section 4 "Manufacturing, Marketing, and Distribution" and Section 5
        "Accounting; Audit; Payment" shall be amended to include the following
        terms:

        *** shall issue a Combined Product Purchase Order ("P.O.") to the
        Foundry, and *** shall be responsible for costs of fabrication. Once
        fabricated, the Foundry will drop-ship the wafers to the designated
        Assembly Facility.

        *** shall issue a P.O. to *** for the purchase of all the wafers
        fabricated from the Foundry.

        *** shall issue a P.O. to the Assembly Facility for the wafer sort, and
        shall be responsible for the costs thereof.

        *** shall then issue a P.O. to the Assembly facility for packaging and
        testing, and will be responsible of the costs thereof.

        *** shall then issue a P.O. to *** for the Combined Product finished
        goods.

        ESS and Counterparty* agree that the manufacturing costs of either wafer
        fabrication, sorting, packaging or test shall be ***. If either party
        receives any rebates, discounts,

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* All references to the counterparty on this page have been replaced with the
term "Counterparty*." Confidential treatment has been requested with respect to
the replaced reference.

*** Certain information on this page has been omitted and filed separately with
the Commission. Confidential treatment has been requested with respect to the
omitted portions.

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        commission or credit from any Product-related manufacturer, each party
        shall be obligated to disclose it (to be treated as ***) to the other
        party immediately.

        ESS and Counterparty* agree to meet on a quarterly basis to reconcile
        accounting and payments due. All accounting for this manufacturing
        venture shall be *** in accordance with Section 5 of the Joint
        Development Agreement.

        *** shall provide *** with ***-month wafer rolling forecasts, and
        provide firm wafer P.O. information to ***. *** agree that *** will
        invoice or/and ship *** all the finished Combined Products within 30
        days of ***'s receipt of these finished Combined Product from the
        testing manufacture.

        The parties agree to work together in developing testing programs for
        the Combined Products, do yield improvement, and resolve any quality
        issues.

        Counterparty* is authorized to sell Combined Products, in die or
        finished-goods form, only to ESS.

        ESS is authorized to sell Combined Products' wafers only to
        Counterparty*. Unless with Counterparty*'s authorized written consent,
        ESS or any third party can not place any Combined Product's P.O. to any
        packaging or testing manufacturer.

        If required, either party will provide direct assistance to the Assembly
        Facility for the assembly, packaging, and testing of the Combined
        Products. In the event Counterparty* decides not to provide the package
        and test Combined Products service, ESS may elect to manufacture the
        Combined Products either itself or with Counterparty*'s prior written
        consent, through a third party. Sales of such Products shall only be
        together with, or for use with ESS/Counterparty* Combined Products.
        Whether such manufacture is by ESS or by a third party, ESS shall pay
        Counterparty* profit shares according to the formula stipulated in the
        Agreement.

        Payment terms are *** for all sales of inventory between the parties.

        3. Exhibit A "Specification" "2. Features of each Combined Product"
shall be amended to include the following terms:

        The Basic Features of the Combined Product shall be judged and
        determined by and from the market mainstream basic
        specification/features products manufactured by major competitors.

        Basic Features Combined Product Sold Ratio=***.

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* All references to the counterparty on this page have been replaced with the
term "Counterparty*." Confidential treatment has been requested with respect to
the replaced reference.

*** Certain information on this page has been omitted and filed separately with
the Commission. Confidential treatment has been requested with respect to the
omitted portions.



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        ESS and Counterparty* agree that the Basic Features Combined Product
        Sold Ratio shall not be less than ***%. If the above Ratio is less than
        ***%, then both parties agree to treat the *** as *** for profit sharing
        calculation purpose; if the above two models' cumulated Ratio is still
        less than ***%, then the *** will be treated as *** too. This rule shall
        apply until the cumulated Ratio is more than ***%.

        4. This Amendment hereby only amends the Joint Development Agreement
Sections 1, 4, 5, and Exhibit A (2) as specified in the above, and is deemed
fully incorporated therein by reference as though set forth in such Agreement in
full. All terms used herein, except where otherwise designated, shall have the
same meanings as they have in the Agreement. In the event of any conflict
between the provisions of this Amendment and the provisions of the Agreement,
the provisions of this Amendment shall prevail.

IN WITNESS WHEREOF, the parties have caused this Amendment to be as of the
Effective Date.

        On behalf of                               On behalf of
        ESS Technology Inc.                        *** Corporation

By:     /s/ Fred S. L. Chan                 By:    /s/ ***
   -----------------------------               ------------------------------

Name:   Fred S. L. Chan                            Name:  ***

Title:  Chairman                                   Title:  President

Date:   18 Jan 2003                                Date:  Jan. 18, 2003



      Both parties also agree to delete the Agreement Exhibit C (4)'s ***.

                                FSLC     ***


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* All references to the counterparty on this page have been replaced with the
term "Counterparty*." Confidential treatment has been requested with respect to
the replaced reference.

*** Certain information on this page has been omitted and filed separately with
the Commission. Confidential treatment has been requested with respect to the
omitted portions.


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