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                                                                  Exhibit 10.64

                                  IMPERIAL BANK
                                   Member FDIC

                           SECURITY AND LOAN AGREEMENT
                              (ACCOUNTS RECEIVABLE)

This Agreement is entered into between Alpha Microsystems, a California
corporation

(herein called "Borrower") and IMPERIAL BANK (herein called "Bank").



1.  Bank hereby commits, subject to all the terms and conditions of this
    Agreement and prior to the termination of its commitment as hereinafter
    provided, to make loans to Borrower from time to time in such amounts as may
    be determined by Bank up to, but not exceeding in the aggregate unpaid
    principal balance, the following Borrowing Base:

              75% of Eligible Accounts and in no event more than $2,000,000.00

2.  The amount of each loan made by Bank to Borrower hereunder shall be debited
    to the loan ledger account of Borrower maintained by Bank (herein called
    "Loan Account") and Bank shall credit the Loan Account with all loan
    repayments made by Borrower. Borrower promises to pay Bank (a) the unpaid
    balance of Borrower's Loan Account on demand and (b) on or before the tenth
    day of each month, interest on the average daily unpaid balance of the Loan
    Account during the immediately preceding month at the rate of two percent (
    2.000 %) per annum in excess of the rate of interest which Bank has
    announced as its prime lending rate ("Prime Rate") which shall vary
    concurrently with any change in such Prime Rate. Interest shall be computed
    at the above rate on the basis of the actual number of days during which the
    principal balance of the loan account is outstanding divided by 360, which
    shall for interest computation purposes be considered one year. Bank at its
    option may demand payment of any or all of the amount due under the Loan
    Account including accrued but unpaid interest at any time. Such notice may
    be given verbally or in writing and should be effective upon receipt by
    Borrower. The amount of interest payable each month by Borrower shall not be
    less than a minimum monthly charge of $ 250.00 . Bank is hereby authorized
    to charge Borrower's deposit account(s) with Bank for all sums due Bank
    under this Agreement.

3.  Requests for loans hereunder shall be in writing duly executed by Borrower
    in a form satisfactory to Bank and shall contain a certification setting
    forth the matters referred to in Section 1, which shall disclose that
    Borrower is entitled to the amount of loan being requested.

4.  As used in this Agreement, the following terms shall have the following
    meanings:

        A. "Accounts" means any right to payment for goods sold or leased, or to
        be sold or to be leased, or for services rendered or to be rendered no
        matter how evidenced, including accounts receivable, contract rights,
        chattel paper, instruments, purchase orders, notes, drains, acceptances,
        general intangibles and other forms of obligations and receivables.

B.      "Collateral" means any and all personal property of Borrower which is
        assigned or hereafter is assigned to Bank as security or in which Bank
        now has or hereafter acquires a security interest.

        C. "Eligible Accounts" means all of Borrowers Accounts excluding,
        however, (1) all Accounts under which payment is not received within 90
        days from any invoice date, (2) all Accounts against which the account
        debtor or any other person obligated to make payment thereon asserts any
        defense, offset, counterclaim or other right to avoid or reduce the
        liability represented by the Account and (3) any Accounts if the account
        debtor or any other person liable in connection therewith is insolvent,
        subject to bankruptcy or receivership proceedings or has made an
        assignment for the benefit of creditors or whose credit standing is
        unacceptable to Bank and Bank has so notified Borrower. Eligible
        Accounts shall only include such accounts as Bank in its sole discretion
        shall determine are eligible from time to time.

5.  Borrower hereby assigns to Bank all Borrowers present and future Accounts,
    including all proceeds due thereunder, all guaranties and security therefor,
    and hereby grants to Bank a continuing security interest in all moneys in
    the Collateral Account referred to in Section 6 hereof, as security for any
    and all obligations of Borrower to Bank, whether now owing or hereafter
    incurred and whether direct, indirect, absolute or contingent. So long as
    Borrower is indebted to Bank or Bank is committed to extend credit to
    Borrower, Borrower will execute and deliver to Bank such assignments,
    including Bank's standard forms of Specific or General Assignment covering
    individual Accounts, notices, financing statements, and other documents and
    papers as Bank may require in order to affirm, effectuate or further assure
    the assignment to Bank of the Collateral or to give any third party,
    including the account debtors obligated on the Accounts, notice of Bank's
    interest in the Collateral.

6.  Until Bank exercises its rights to collect the Accounts pursuant to
    paragraph 10, Borrower will collect with diligence ail Borrower's Accounts,
    provided that no legal action shall be maintained thereon or in connection
    therewith without Bank's prior written consent. Any collection of Accounts
    by Borrower, whether in the form of cash, checks, notes, or other
    instruments for the payment of money (properly endorsed or assigned where
    required to enable Bank to collect same), shall be in trust for Bank, and
    Borrower shall keep ail such collections separate and apart from all other
    funds and property so as to be capable of identification as the property of
    Bank and deliver said collections daily to Bank in the identical form
    received. The proceeds of such collections when received by Bank may be
    applied by Bank directly to the payment of Borrower's Loan Account or any
    other obligation secured hereby. Any credit given by Bank upon receipt of
    said proceeds shall be conditional credit subject to collection. Returned
    items at Bank's option may be charged to Borrower's general account. All
    collections of the Accounts shall be set forth on an itemized schedule,
    showing the name of the account debtor, the amount of each payment and such
    other information as Bank may request.


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7.  Until Bank exercises its rights to collect the Accounts pursuant to
    paragraph 10, Borrower may continue its present policies with respect to
    returned merchandise and adjustments. However, Borrower shall immediately
    notify Bank of all cases involving returns, repossessions, and loss or
    damage of or to merchandise represented by the Accounts and of any credits,
    adjustments or disputes arising in connection with the goods or services
    represented by the Accounts and, in any of such events, Borrower will
    immediately pay to Bank from its own funds (and not from the proceeds of
    Accounts or Inventory) for application to Borrower's Loan Account or any
    other obligation secured hereby the amount of any credit for such returned
    or repossessed merchandise and adjustments made to any of the Accounts.

8.  Borrower represents and warrants to Bank: (i) If Borrower is a corporation,
    that Borrower is duly organized and existing in the State of its
    incorporation and the execution, delivery and performance hereof are within
    Borrower's corporate powers, have been duly authorized and are not in
    conflict with law or the terms of any charter, by-law or other incorporation
    papers, or of any indenture, agreement or undertaking to which Borrower is a
    party or by which Borrower is found or affected; (ii) Borrower is, or at the
    time the collateral becomes subject to Bank's security interest will be, the
    true and lawful owner of and has, or at the time the Collateral becomes
    subject to Bank's security interest will have, good and clear title to the
    Collateral, subject only to Bank's rights therein; (iii) Each Account is, or
    at the time the Account comes into existence will be, a true and correct
    statement of a bona fide indebtedness incurred by the debtor named therein
    in the amount of the Account for either merchandise sold or delivered (or
    being held subject to Borrower's delivery instructions) to, or services
    rendered, performed and accepted by, the account debtor; (iv) That there are
    or will be no defenses, counterclaims, or setoffs which may be asserted
    against the Accounts; and (v) any and all financial information, including
    information relating to the Collateral, submitted by Borrower to Bank,
    whether previously or in the future, is or will be true and correct.

9.  Borrower will: (i) Furnish Bank from time to time such financial statements
    and information as Bank may reasonably request and inform Bank immediately
    upon the occurrence of a material adverse change therein; (ii) Furnish Bank
    periodically, in such form and detail and at such times as Bank may require,
    statements showing aging and reconciliation of the Accounts and collections
    thereon; (iii) Permit representatives of Bank to inspect the Borrower's
    books and records relating to the Collateral and make extracts therefrom at
    any reasonable time and to arrange for verification of the Accounts, under
    reasonable procedures, acceptable to Bank, directly with the account debtors
    or otherwise at Borrower's expense; (iv) Promptly notify Bank of any
    attachment or other legal process levied against any of the Collateral and
    any information received by Borrower relative to the Collateral, including
    the Accounts, the account debtors or other persons obligated in connection
    therewith, which may in any way affect the value of the Collateral or the
    rights and remedies of Bank in respect thereto; (v) Reimburse Bank upon
    demand for any and all legal costs, including reasonable attorneys' fees,
    and other expense incurred in collecting any sums payable by Borrower under
    Borrower's Loan Account or any other obligation secured hereby, enforcing
    any term or provision of this Security Agreement or otherwise or in the
    checking, handling and collection of the Collateral and the preparation and
    enforcement of any agreement relating thereto; (vi) Notify Bank of each
    location and of each office of Borrower at which records of Borrower
    relating to the Accounts are kept; (vii) Provide, maintain and deliver to
    Bank policies insuring the Collateral against loss or damage by such risks
    and in such amounts, forms and companies as Bank may require and with loss
    payable solely to Bank, and, in the event Bank takes possession of the
    Collateral, the insurance policy or policies and any unearned or returned
    premium thereon shall at the option of Bank become the sole property of
    Bank, such policies and the proceeds of any other insurance covering or in
    any way relating to the Collateral, whether now in existence or hereafter
    obtained, being hereby assigned to Bank; (viii) In the event the unpaid
    balance of Borrower's Loan Account shall exceed the maximum amount of
    outstanding loans to which Borrower is entitled under Section 1 hereof,
    Borrower shall immediately pay to Bank, from its own funds and not from the
    proceeds of Collateral, for credit to Borrower's Loan Account the amount of
    such excess.

10. Bank may at any time, without prior notice to Borrower, collect the Accounts
    and may give notice of assignment to any and all account debtors, and
    Borrower does hereby make, constitute and appoint Bank its irrevocable, true
    and lawful attorney with power to receive, open and dispose of all mail
    addressed to Borrower, to endorse the name of Borrower upon any checks or
    other evidences of payment that may come into the possession of Bank upon
    the Accounts to endorse the name of the undersigned upon any document or
    instrument relating to the Collateral; in its name or otherwise, to demand,
    sue for, collect and give acquittances for any and all moneys due or to
    become due upon the Accounts; to compromise, prosecute or defend any action,
    claim or proceeding with respect thereto; and to do any and all things
    necessary and proper to carry out the purpose herein contemplated.

11. Until Borrower's Loan Account and ail other obligations secured hereby
    shall have been repaid in full, Borrower shall not sell, dispose of or
    grant a security interest in any of the Collateral other than to Bank, or
    to execute any financing statements covering the collateral in favor of any
    secured party or person other than Bank.

12. Should: (i) Default be made in the payment of any obligation, or breach be
    made in any warranty, statement, promise, term or condition, contained
    herein or hereby secured; (ii) Any statement or representation made for the
    purpose of obtaining credit hereunder prove false; (iii) Bank deem the
    Collateral inadequate or unsafe or in danger of misuse; (iv) Borrower become
    insolvent or make an assignment for the benefit of creditors; or (v) Any
    proceeding be commenced by or against Borrower under any bankruptcy,
    reorganization, arrangement, readjustment of debt or moratorium law or
    statute; then in any such event, Bank may, at its option and without demand
    first made and without notice to Borrower, do any one or more of the
    following: (a) Terminate its obligation to make loans to Borrower as
    provided in Section 1 hereof; (b) Declare all sums secured hereby
    immediately due and payable; (c) Immediately take possession of the
    Collateral wherever it may be found, using all-necessary force so to do, or
    require Borrower to assemble the Collateral and make it available to Bank at
    a place designated by Bank which is reasonably convenient to Borrower and
    Bank, and Borrower waives all claims for damages due to or arising from or
    connected with any such taking; (d) Proceed in the foreclosure of Bank's
    security interest and sale of the Collateral in any manner permitted by law,
    or provided for herein; (e) Sell, lease or otherwise dispose of the
    Collateral at public or private sale, with or without having the Collateral
    at the place of sale, and upon terms and in such manner as Bank may
    determine, and Bank may purchase same at any such sale; (f) Retain the
    Collateral in full satisfaction of the obligations secured thereby; (g)
    Exercise any remedies of a secured party under the Uniform Commercial Code.
    Prior to any such disposition, Bank may, at as option, cause any of the
    Collateral to be repaired or reconditioned in such manner and to such extent
    as Bank may deem advisable, and any sums expended therefor by Bank shall be
    repaid by Borrower and secured hereby. Bank shall have the right to enforce
    one or more remedies hereunder successively or concurrently, and any such
    action shall not estop or prevent Bank from pursuing any funkier remedy
    which it may have hereunder or by law. If a sufficient sum is not realized
    from any such disposition of Collateral to pay all obligations secured by
    this Security Agreement, Borrower hereby promises and agrees to pay Bank any
    deficiency.

13. If any writ of attachment, garnishment, execution or other legal process be
    issued against any property of Borrower, or if any assessment for taxes
    against Borrower, other than real property, is made by the Federal or State
    government or any department thereof, the obligation of Bank to make 


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    loans to Borrower as provided in Section 1 hereof shall immediately
    terminate and the unpaid balance of the Loan Account, all other obligations
    secured hereby and all other sums due hereunder shall immediately become due
    and payable without demand, presentment or notice.

14. Borrower authorizes Bank to destroy all invoices, delivery receipts, reports
    and other types of documents and records submitted to Bank in connection
    with the transactions contemplated herein at any time subsequent to four
    months from the time such items are delivered to Bank.

15. Nothing herein shall in any way limit the effect of the conditions set Forth
    in any other security or other agreement executed by Borrower, but each and
    every condition hereof shall be in addition thereto.

*16. Additional Provisions: The Addendum or Exhibit "A" attached (and all
    amendments thereto and replacements therefor) Is incorporated herein by this
    reference.

Executed this 9th day of June, 1998

                                                  Alpha MicroSystems
                                                  ------------------
                                                  (Name of Borrower)


       IMPERIAL BANK                 BY:
                                         --------------------------------------
                                             (Authorized Signature and Title)




BY:                                  BY:
   --------------------------------      --------------------------------------
   Leila Ghoroghchi, Vice President          (Authorized Signature and Title)


*If none, insert  "None"





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