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                                                                   EXHIBIT 10.66

                              ESS TECHNOLOGY, INC.

                              AMENDED AND RESTATED
                             STOCK OPTION AGREEMENT

      1.    OPTION. This Amended and Restated Stock Option Agreement sets forth
the terms applicable to the option (the "Option") previously granted by ESS
Technology, Inc., a California corporation (the "Company"), to the optionee (the
"Optionee") named in the Notice of Grant of Stock Options and Option Agreement
(the "Notice") on the date set forth therein. This option provides the Optionee
the right to purchase the total number of shares of common stock of the Company
set forth in the Notice (the "Shares") at the exercise price per Share set forth
in the Notice (the "Exercise Price") subject to the terms and conditions of the
Notice, this Agreement and the plan identified in the Notice (the ESS
Technology, Inc. 1997 Equity Incentive Plan or the ESS Technology, Inc. 1995
Equity Incentive Plan, the "Plan"), which Plan is incorporated in this Agreement
by reference. Unless otherwise defined in this Agreement, the terms used in this
Agreement shall have the meanings defined in the Plan.

      2.    DESIGNATION OF OPTION. This Option is intended to be a nonstatutory
stock option.

      3.    EXERCISE OF OPTION. This Option shall be exercisable during its term
in accordance with the vesting schedule set out in the Notice and with the
applicable provisions of the Plan as follows:

            (a)   RIGHT TO EXERCISE.

                  (i)   This Option may not be exercised for a fraction of a
share.

                  (ii)  In the event of Optionee's death, disability or other
termination of service, the exercisability of the Option is governed by Section
5 below, subject to the limitations contained in this Section 3.

                  (iii) In no event may this Option be exercised after the
Expiration Date of the Option as set forth in the Notice.

            (b)   METHOD OF EXERCISE.

                  (i)   This Option shall be exercisable by delivering to the
Company a written notice of exercise (in the form attached hereto as Exhibit A
or in any other form of notice approved by the Committee) which shall state
Optionee's election to exercise the Option, the number of Shares in respect of
which the Option is being exercised, and such other representations and
agreements as to the holder's investment intent with respect to such Shares as
may be required by the Company pursuant to the provisions of the Plan. Such
written notice shall be signed by Optionee and shall be delivered to the Company
by such means as are determined by the Committee in its discretion to constitute
adequate delivery. The written notice shall be accompanied by payment of the
Exercise Price. This Option shall be deemed to be

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exercised upon receipt by the Company of such written notice accompanied by the
Exercise Price.

                  (ii)  As a condition to the exercise of this Option, Optionee
agrees to make adequate provision for federal, state or other tax withholding
obligations, if any, which arise upon the vesting or exercise of the Option, or
disposition of Shares, whether by withholding, direct payment to the Company, or
otherwise.

                  (iii) The Company is not obligated, and will have no liability
for failure, to issue or deliver any Shares upon exercise of the Option unless
such issuance or delivery would comply with the Applicable Laws, with such
compliance determined by the Company in consultation with its legal counsel.
This Option may not be exercised until such time as the Plan has been approved
by the stockholders of the Company, or if the issuance of such Shares upon such
exercise or the method of payment of consideration for such shares would
constitute a violation of any applicable federal or state securities or other
law or regulation, including any rule under Part 221 of Title 12 of the Code of
Federal Regulations as promulgated by the Federal Reserve Board. As a condition
to the exercise of this Option, the Company may require Optionee to make any
representation and warranty to the Company as may be required by the Applicable
Laws. Assuming such compliance, for income tax purposes the Shares shall be
considered transferred to Optionee on the date on which the Option is exercised
with respect to such Shares.

      4.    METHOD OF PAYMENT. Payment of the Exercise Price shall be by any of
the following, or a combination of the following, at the election of Optionee:

            (a)   cash or check; or

            (b)   delivery of a properly executed exercise notice together with
irrevocable instructions to a broker approved by the Company to deliver promptly
to the Company the amount of sale or loan proceeds required to pay the exercise
price; or

            (c)   surrender of other shares of common stock of the Company that:

                  (i)   either have been owned by Optionee for more than six (6)
      months on the date of surrender or were not acquired, directly or
      indirectly, from the Company, and

                  (ii)  have a Fair Market Value on the date of surrender equal
      to the aggregate exercise price of the Shares as to which said Option
      shall be exercised.

      5.    TERMINATION OF RELATIONSHIP. In the event of the termination of
Optionee's Continuous Service Status for any reason (the date of such
termination is referred to herein as the "Termination Date") or the death of
Optionee within three months after Optionee's Termination Date, Optionee (or, in
the case of Optionee's death, Optionee's estate or any person who acquired the
right to exercise the Option by bequest or inheritance), may, but only within 3
years of the Termination Date, exercise this Option to the extent Optionee was
entitled to exercise it as of the Termination Date. To the extent that Optionee
is not entitled to exercise this Option as of the Termination Date, or if
Optionee does not exercise this Option within the time specified herein,

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the Option shall terminate. Notwithstanding anything stated herein to the
contrary, in no event may the Option be exercised after the Expiration Date of
the Option as set forth in the Notice.

      6.    NON-TRANSFERABILITY OF OPTION. This Option may not be transferred in
any manner otherwise than by will or by the laws of descent or distribution and
may be exercised during the lifetime of Optionee only by him or her. The terms
of this Option shall be binding upon the executors, administrators, heirs,
successors and assigns of Optionee.

      7.    EFFECT OF AGREEMENT. Optionee acknowledges receipt of a copy of the
Plan, the Notice and this Agreement and represents that he or she is familiar
with the terms and provisions thereof (and has had an opportunity to consult
counsel regarding the Option terms), and hereby accepts this Option and agrees
to be bound by its contractual terms as set forth herein and in the Notice and
the Plan. Optionee hereby agrees to accept as binding, conclusive and final all
decisions and interpretations of the Committee regarding any questions relating
to the Option. In the event of a conflict between the terms and provisions of
the Plan and the terms and provisions of the Notice and this Agreement, the Plan
terms and provisions shall prevail. The Option, including the Plan and the
Notice, constitutes the entire agreement between Optionee and the Company on the
subject matter hereof and supersedes all proposals, written or oral, and all
other communications between the parties relating to such subject matter.

      8.    NO ADDITIONAL EMPLOYMENT RIGHTS. Optionee understands and agrees
that the vesting of Shares pursuant to the vesting schedule is earned only by
continuing as an employee or consultant at the will of the Company or, to the
extent applicable, its Parent, Subsidiary or Affiliate (not through the act of
being hired, being granted this Option or acquiring Shares under this
Agreement). Optionee further acknowledges and agrees that nothing in this
Agreement, nor in the Plan which is incorporated in this Agreement by reference,
shall confer upon Optionee any right with respect to continuation as an employee
or consultant with the Company, its Parent, Subsidiaries or Affiliates, nor
shall it interfere in any way with his or her right or the Company's (or the
Parents, Subsidiaries, or Affiliates) right to terminate his or her employment
or consulting relationship at any time, with or without cause.

      9.    DEFINITIONS.

            (a)   "Applicable Laws" means all applicable laws, rules and
      regulations, including, but not limited to, U.S. state corporate laws,
      U.S. federal and applicable state securities laws, the Internal Revenue
      Code of 1986, as amended, any Stock Exchange rules or regulations and the
      applicable laws of any other country or jurisdiction where awards are
      granted under the Plan or where Plan participants reside or provide
      services to the Company or any Parent, Subsidiary or Affiliate, as such
      laws, rules, regulations and requirements shall be in place from time to
      time.

            (b)   "Continuous Service Status" means the absence of any
      interruption or termination of service as an employee or consultant.
      Continuous Service Status as an employee or consultant shall not be
      considered interrupted in the case of: (i) sick leave; (ii) military
      leave; (iii) any other leave of absence approved by the Committee,
      provided that such leave is for a period of not more than ninety days,
      unless reemployment upon

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      the expiration of such leave is guaranteed by contract or statute, or
      unless provided otherwise pursuant to Company policy adopted from time to
      time; or (iv) in the case of transfers between locations of the Company or
      between the Company, its Parents, Subsidiaries, Affiliates or their
      respective successors. A change in status from an employee to a consultant
      or from a consultant to an employee will not constitute an interruption of
      Continuous Service Status.

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                                    EXHIBIT A

                               NOTICE OF EXERCISE

To:         ESS Technology, Inc.
Attn:       Stock Option Administrator
Subject:    Notice of Intention to Exercise Stock Option

      This is official notice that the undersigned ("Optionee") intends to
exercise Optionee's option (Option Number _________) to purchase
___________________ shares of ESS Technology, Inc. common stock, under and
pursuant to the Notice of Grant of Stock Options and Option Agreement ("Notice")
dated ______________________, the plan identified in the Notice, and the Amended
and Restated Stock Option Agreement, as follows:

            Grant Number:      _______________________________________

            Date of Purchase:  _______________________________________

            Number of Shares:  _______________________________________

            Purchase Price:    _______________________________________

            Method of Payment
            of Purchase Price: _______________________________________

      The shares should be issued as follows:

            Name:     _______________________________________

            Address:  _______________________________________

                      _______________________________________

                      _______________________________________

            Signed:   _______________________________________

            Date:     _______________________________________