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                                                                   Exhibit 10.73




SILICON VALLEY BANK

AMENDMENT TO LOAN AGREEMENT

BORROWER:      ALPHA MICROSYSTEMS
ADDRESS:       2722 SOUTH FAIRVIEW STREET
               SANTA ANA, CALIFORNIA  92704

DATED AS OF:   OCTOBER 11, 1996

     THIS AMENDMENT TO LOAN AGREEMENT is entered into between SILICON VALLEY
BANK ("Silicon") and the borrower named above (the "Borrower").

     The Parties agree to amend the Loan and Security Agreement between them
(the "Loan Agreement") dated July 10, 1995, as amended from time to time,
effective as of the date hereof.  (Capitalized terms used but not defined in
this Amendment, shall have the meanings set forth in the Loan Agreement.)

     1.   MODIFICATION TO MATURITY DATE.  The Maturity Date as set forth in the
Schedule to the Loan Agreement is hereby amended to be "October 10, 1997".

     2.   MODIFICATION TO FINANCIAL COVENANTS.  The section of the Schedule to
the Loan Agreement entitled "Financial Covenants (Section 4.1)" is hereby
amended in its entirety to read as follows:

     "FINANCIAL COVENANTS 
        (Section 4.1):           Borrower shall comply with all of the 
                                 following covenants.  Compliance shall be 
                                 determined as of the end of each
                                 month, except as otherwise specifically
                                 provided below:

     QUICK ASSET RATIO:          Borrower shall maintain a ratio of "Quick
                                 Assets" to current liabilities of not less than
                                 3.00 to 1.

     TANGIBLE NET WORTH:         Borrower shall maintain a tangible net worth of
                                 not less than $12,750,000.

     DEBT TO TANGIBLE 
     NET WORTH RATIO:            Borrower shall maintain a ratio of total 
                                 liabilities to tangible net worth of not more 
                                 than .50 to 1.

     PROFITABILITY               Borrower shall not incur a loss (after taxes)
                                 for the fiscal year ending February 28, 1997 in
                                 excess of $2,200,000.  Thereafter, Borrower
                                 shall not incur any losses (after taxes) in any
                                 fiscal quarter, other than for a loss (after
                                 taxes) in a single fiscal quarter during any
                                 fiscal year if the amount of such loss does not
                                 exceed 
                             

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                                 $250,000. For purposes of this financial
                                 covenant, capitalized software is to be
                                 considered an expense of the Borrower.

     DEFINITIONS:                "Current assets," and "current liabilities"
                                 shall have the meanings ascribed to them in
                                 accordance with generally accepted accounting
                                 principles.

                                 "Tangible net worth" means the excess of total
                                 assets over total liabilities, determined in
                                 accordance with generally accepted accounting
                                 principles, excluding however all assets which
                                 would be classified as intangible assets under
                                 generally accepted accounting principles,
                                 including without limitation goodwill,
                                 licenses, patents, trademarks, trade names,
                                 copyrights, capitalized software and
                                 organizational costs, licences and franchises.

                                 "Quick Assets" means cash on hand or on deposit
                                 in banks, readily marketable securities issued
                                 by the United States, readily marketable
                                 commercial paper rated "A-1" by Standard &
                                 Poor's Corporation (or a similar rating by a
                                 similar rating organization), certificates of
                                 deposit and banker's acceptances, and accounts
                                 receivable (net of allowance for doubtful
                                 accounts).

     DEFERRED REVENUES:          For purposes of the above quick asset ratio,
                                 deferred revenues shall not be counted as
                                 current liabilities.  For purposes of the above
                                 debt to tangible net worth ratio, deferred
                                 revenues shall not be counted in determining
                                 total liabilities but shall be counted in
                                 determining tangible net worth for purposes of
                                 such ratio. For all other purposes deferred
                                 revenues shall be counted as liabilities in
                                 accordance with generally accepted accounting
                                 principles.

     SUBORDINATED DEBT:          "Liabilities" for purposes of the foregoing
                                 covenants do not include indebtedness which is
                                 subordinated to the indebtedness to Silicon
                                 under a subordination agreement in form
                                 specified by Silicon or by language in the
                                 instrument evidencing the indebtedness which is
                                 acceptable to Silicon."


     3.  NEW WARRANTS.  The Borrower shall provide Silicon with five-year
warrants to purchase 25,000 shares of Common stock of the Borrower, at a price
per share equal to the market price per share as reflected on the date prior to
the Borrower's execution of this Amendment, on the terms and conditions in the
Warrant to Purchase Stock and related documents being executed concurrently with
this Amendment, which Warrant shall be in addition to the Warrant previously
issued by the Borrower in favor of Silicon.

     4.  FEE.  Borrower shall pay to Silicon a facility fee in the amount of
$7,500 in connection with this Amendment, which shall be in addition to all
interest payable under the Loan Agreement and all other amounts due thereunder,
and which shall not be refundable.

     5.  REPRESENTATIONS TRUE.  Borrower represents and warrants to Silicon that
all representations and warranties set forth in the Loan Agreement, as amended
hereby, are true and correct.

     6.  GENERAL PROVISIONS. This Amendment, the Loan Agreement, any prior
written amendments to the Loan Agreement signed by Silicon and the Borrower, and
the other written documents and agreements between Silicon and the Borrower set
forth in full all of the







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representations and agreements of the parties with respect to the subject matter
hereof and supersede all prior discussions, representations, agreements and
understandings between the parties with respect to the subject hereof.  Except
as herein expressly amended, all of the terms and provisions of the Loan
Agreement, and all other documents and agreements between Silicon and the
Borrower shall continue in full force and effect and the same are hereby
ratified and confirmed.



        BORROWER:

        ALPHA MICROSYSTEMS

        BY
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             PRESIDENT OR VICE PRESIDENT

        BY
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             SECRETARY OR ASS'T SECRETARY



        SILICON:

        SILICON VALLEY BANK

        BY
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        TITLE
              -------------------------------




                              GUARANTOR'S CONSENT

         The undersigned guarantor acknowledges that its consent to the
foregoing Amendment is not required, but the undersigned nevertheless does
hereby consent to the foregoing Amendment and to the documents and agreements
referred to therein and to all future modifications and amendments thereto, and
to any and all other present and future documents and agreements between or
among the foregoing parties. Nothing herein shall in any way limit any of the
terms or provisions of the Continuing Guaranty executed by the undersigned in
favor of Silicon, which is hereby ratified and affirmed and shall continue in
full force and effect.

                                        ALPHAHEALTHCARE, INC.

                                        By: 
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                                        Title:
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