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                                                                    EXHIBIT 10.X


                          LOAN MODIFICATION AGREEMENT


      This Loan Modification Agreement is entered into as of March 4, 1998, by
and between YieldUP International Corporation ("Borrower") whose address is 117
Easy Street, Mountain View, CA 94043 and Silicon Valley Bank ("Bank") whose
address is 3003 Tasman Drive, Santa Clara, CA 95054.

1.    DESCRIPTION OF EXISTING INDEBTEDNESS: Among other indebtedness which may
be owing by Borrower to Bank, Borrower is indebted to Bank pursuant to, among
other documents, an Amended and Restated Loan and Security Agreement, dated
March 5, 1997, as may be amended from time to time, (the "Loan Agreement"). The
Loan Agreement provided for, among other things, a Committed Revolving Line in
the original principal amount of Two Million Dollars ($2,000,000), (the
"Revolving Facility") and a Term Loan in the amended principal amount of Six
Hundred Thirty Thousand Dollars ($630,000) ("Term Loan"). Defined terms used
but not otherwise defined herein shall have the same meanings as in the Loan
Agreement.

Hereinafter, all indebtedness owing by Borrower to Bank shall be referred to as
the "Indebtedness."

2.    DESCRIPTION OF COLLATERAL AND GUARANTIES. Repayment of the Indebtedness
is secured by the Collateral as described in the Loan Agreement and in the
Collateral Assignment, Patent Mortgage and Security Agreement dated March 5,
1997 (the "IP Agreement"). Notwithstanding the foregoing, pursuant to this Loan
Modification Agreement, Bank shall release its security interest under the IP
Agreement in consideration of Borrower executing a Negative Pledge Agreement
stating it shall not pledge its intellectual property to any party without
written permission by Bank.

Hereinafter, the above-described security documents and guaranties, together
with all other documents securing repayment of the Indebtedness shall be
referred to as the "Security Documents." Hereinafter, the Security Documents,
together with all other documents evidencing or securing the Indebtedness
shall be referred to as the "Existing Loan Documents."

3.    DESCRIPTION OF CHANGE IN TERMS.

      A.    Modification(s)) to Loan Agreement

            1.    The following terms under Section 1.1 entitled "Definitions"
                  are hereby amended as follows:

                  "Committed Revolving Line" means Four Million Dollars 
                  ($4,000,000).

                  "Revolving Maturity Date" means March 3, 1999.

                  Item "(1)" under "Eligible Accounts" means Accounts with
                  respect to an account debtor, including Subsidiaries and
                  Affiliates, whose total obligations to Borrower exceed
                  twenty-five percent (25%) of all Accounts, to the extent such
                  obligations exceed the aforementioned percentage, provided
                  however, (i) a thirty-five percent (35%) concentration limit
                  is allowed for each of Applied Materials, Intel, Micron, Komag
                  and Matsushita, or (ii) as otherwise approved in writing by
                  Bank.

                  "Eligible Foreign Accounts" are Eligible Accounts for which
                  the account debtor does not have its principal place of
                  business in the United States but are: (1) covered by credit
                  insurance satisfactory to Bank, less any deductible; or (2)
                  supported by letter(s) of credit acceptable to Bank; or (3)
                  that Bank approves in writing.



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            2.    The following terms are hereby incorporated in to Section 1.1
                  entitled "Definitions":

                  "EQUIPMENT AVAILABILITY END DATE" is defined in Section 2.1.5.

                  "EQUIPMENT ADVANCE" is defined in Section 2.1.5.

                  "COMMITTED EQUIPMENT LINE" means Five Hundred Thousand Dollars
                  ($500,000).

                  "EQUIPMENT MATURITY DATE" is defined in Section 2.1.5.

                  "CAPITALIZED PRODUCT DEVELOPMENT COSTS" are all costs
                  associated with the development of Borrower's product,
                  including, but not limited to software, that are not recorded
                  as an expense and have been classified as an asset account.

                  "CREDIT EXTENSION" is each Advance, Equipment Advance, Letter
                  of Credit, or any other extension of credit by Bank for
                  Borrower's benefit.

            3.    The first sentence in the first paragraph under Section 2.1
                  entitled "Advances" is hereby amended to read as follows:

                  Subject to and upon the terms and conditions of this
                  Agreement, Bank agrees to make Advances to Borrower in an
                  aggregate amount not to exceed (i) the lesser of (A) the
                  Committed Revolving Line minus the Cash Management Services
                  Sublimit or (B) the Borrowing Base, whichever is less, minus
                  (ii) the amount of all outstanding Letters of Credit
                  (including drawn but unreimbursed Letters of Credit).

            4.    Item "(a)" under Section 2.1.1 entitled "Letters of Credit"
                  is hereby amended to read as follows:

                  (a) Subject to the terms and conditions of this Agreement,
                  Bank agrees to issue or cause to be issued letters of credit
                  for the account of Borrower in an aggregate face amount not to
                  exceed (i) the lesser of the Committed Revolving Line or the
                  Borrowing Base minus (ii) the outstanding principal balance of
                  the Advances minus the Cash Management Sublimit; however, the
                  face amount of outstanding Letters of Credit (including drawn
                  but unreimbursed Letters of Credit and any Letter of Credit
                  Reserve) may not exceed $4,000,000. Each such Letter of Credit
                  shall have an expiry date no later than ninety (90) days after
                  the Revolving Maturity Date provided that Borrower's letter of
                  credit reimbursement obligation shall be secured by cash on
                  terms acceptable to Bank at any time after the Revolving
                  Maturity Date if the term of this Agreement is not extended by
                  Bank. All such letters of credit shall be, in form and
                  substance, acceptable to Bank in its sole discretion and
                  shall be subject to the terms and condition of Bank's form of
                  application and letter of credit agreement.

            5.    The following Section is hereby incorporated into the Loan
                  Agreement:

                  2.1.4  CASH MANAGEMENT SERVICES SUBLIMIT.

                  Borrower may use up to $500,000 for Bank's Cash Management
                  Services, which may include merchant services, direct deposit
                  of payroll, business credit card, and check cashing services
                  identified in various cash management services



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                  agreements related to such services (the "Cash Management
                  Services"). All amounts Bank pays for any Cash Management
                  Services will be treated as Advances under the Committed
                  Revolving Line.

            6.    The following Section is hereby incorporated into the Loan
                  Agreement:

                  2.1.5  EQUIPMENT ADVANCES.

                  Through March 4, 1999 (the "Equipment Availability End Date"),
                  Bank will make advances ("Equipment Advance" and,
                  collectively, "Equipment Advances") not exceeding the
                  Committed Equipment Line. The Equipment Advances may only be
                  used to finance Equipment leasehold improvements and may not
                  exceed 100% of the invoice amount excluding taxes, shipping,
                  warranty charges, freight discounts and installation expense.

                  Interest accrues from the date of each Equipment Advance at
                  the rate in Section 2.3.1 and is payable monthly, beginning
                  April 4, 1998, until the Equipment Availability End Date
                  occurs. Equipment Advances outstanding on the Equipment
                  Availability End Date are payable in 36 equal monthly
                  installments of principal, plus accrued interest, beginning on
                  the 4th of each month following the Equipment Availability End
                  Date and ending on March 4, 2002 (the "Equipment Maturity
                  Date"). Equipment Advances when repaid may not be reborrowed.

                  To obtain an Equipment Advance, Borrower must notify Bank (the
                  notice is irrevocable) by facsimile no later than 3:00 p.m.
                  Pacific time 1 Business Day before the day on which the
                  Equipment Advance is to be made. The notice in the form of
                  Exhibit B (Payment/Advance Form) must be signed by a
                  Responsible Officer or designee and include a copy of the
                  invoice for the Equipment being financed.

            7.    Section 2.3.1 entitled "Interest Rate" is hereby amended in
                  its entirety to read as follows:

                  (a) Any Advances under the Committed Revolving Line shall bear
                  interest at a rate equal to one and one quarter (1.250)
                  percentage points above the Prime Rate.

                  (b) Any Advances under the Term Loan shall bear interest at a
                  rate equal to two and one quarter (2.250) percentage points
                  above the Prime Rate.

                  (c) Any Equipment Advances under the Committed Equipment Line
                  shall bear interest at a rate equal to one and three quarters
                  (1.750) percentage points above the Prime Rate.

            8.    The first sentence in Section 2.7 entitled "Term" is hereby
                  amended to read as follows:

                  Except as otherwise set forth herein, this Agreement shall
                  become effective on the Closing Date and, subject to Section
                  12.7, shall continue in full force and effect for a term
                  ending on the later of the Revolving Maturity Date or the Term
                  Loan Maturity Date or the Equipment Maturity Date.



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 9.  The certificate of deposit number 8800015809 securing the Term Loan 
     Advances is hereby no longer required and shall not be a part of the
     Collateral.

10.  Item "(a)" in the first paragraph under Section 6.3 entitled "Financial
     Statements, Reports, Certificates" is hereby amended to read as follows:

     . . . (a) at such times as outstanding Obligations exist, as soon as
     available, but in an event within thirty (30) days after the end of each
     month, a company prepared consolidated balance sheet and income statement
     covering Borrower's consolidated operations during such period, certified
     by an officer of Borrower reasonably acceptable to Bank; . . .

11.  The second paragraph under Section 6.3 entitled "Financial Statements,
     Reports, Certificates" is hereby amended to read as follows:

     Within twenty (20) days after the last day of each month, Borrower shall
     deliver to Bank a Borrowing Base Certificate signed by a Responsible
     Officer together with aged listings of accounts receivable and accounts
     payable.

12.  The fourth paragraph under Section 6.3 entitled "Financial Statements,
     Reports, Certificates" is hereby amended to read as follows:

     Bank shall have a right from to time hereafter to audit Borrower's
     Accounts at Borrower's expense, provided that such audits will be
     conducted no more often than once each fiscal year unless an Event of
     Default has occurred and is continuing.

13.  Section 6.8 entitled "Quick Ratio" is hereby amended in its entirety to
     read as follows:

     Borrower shall maintain, as of the last day of each calendar month, a
     ratio of Quick Assets to Current Liabilities of at least 1.75 to 1.00.

14.  Section 6.10 entitled "Tangible Net Worth" is hereby deleted and replaced
     with the words, "Intentionally left blank."

15.  Section 6.11 entitled "Profitability" is hereby amended in its entirety to
     read as follows:

     Borrower shall be profitable on a quarterly and an annual basis, provided,
     however, Borrower may suffer a loss not to exceed Five Hundred Thousand
     Dollars ($500,000) in a maximum of 1 quarter during any fiscal year.

16.  Section 6.12 entitled "Minimum Liquidity" is hereby amended in its
     entirety to read as follows:

     Borrower shall maintain, as of the last calendar day of each month, a
     ratio of unrestricted cash (and equivalents) plus net availability under
     the Committed Revolving Line divided by Term Loan and Equipment Advances
     outstandings of not less than 2.00 to 1.00. If Borrower maintains, for 2
     consecutive fiscal quarters, a ratio of earnings after tax less
     Capitalized Product Development Costs plus interest, depreciation and
     amortization for the specified period on an



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                    annualized basis to current maturities of long term debt
                    and capitalized leases, plus interest expense annualized of
                    at least 1.75 to 1.00 (the "Debt Service Coverage"), then
                    the Debt Service Coverage shall replace the Liquidity
                    Coverage.

               17.  The term "Advances" in the last sentence in Sections 8.4.
                    8.5 and 8.8 shall be amended to read "Certain Extensions".

               18.  Borrower shall issue to Bank a warrant to purchase 2,439
                    shares of Borrower's Common stock, with an initial exercise
                    price of $10.25 per share. Such warrant shall be on Bank's
                    form, contain registration rights and antidilution
                    provisions and shall be for a term of five years.

     B.   Release of IP Agreement.

          1.   As an accommodation to Borrower and for good and valuable
               consideration, including Bank's agreement to release its
               security interest in all of Borrower's Copyrights, Patents and
               Trademarks, Bank, with this Loan Modification Agreement, has
               agreed to release its security interest in Borrower's
               Copyrights, Patents and Trademarks granted under the IP
               Agreement. In consideration of such release of security
               interest, Borrower shall execute a negative pledge agreement
               covering all of Borrower's Copyrights, Patents and Trademarks
               (the "Negative Pledge Agreement"). Such Negative Pledge
               Agreement shall include Borrower's agreement that it shall not
               encumber any of its Copyrights, Patents and Trademarks without
               the prior written consent of Bank.

4.   CONSISTENT CHANGES. The Existing Loan Documents are hereby amended wherever
necessary to reflect the changes described above.

5.   PAYMENT OF LOAN FEE. Borrower shall pay to Bank the sum of fees as
follows: (a) Twenty Thousand Dollars ($20,000) (the "Revolving Loan Fee") plus
(b) One Thousand Two Hundred Fifty Dollars ($1,250) (the "Equipment Advance
Fee") plus (c) all out-of-pocket expenses.

6.   NO DEFENSES OF BORROWER. Borrower (and each guarantor and pledgor signing
below) agrees that, as of the date hereof, it has no defenses against the
obligations to pay any amounts under the indebtedness.

7.   CONTINUING VALIDITY. Borrower (and each guarantor and pledgor signing
below) understands and agrees that in modifying the existing indebtedness, Bank
is relying upon Borrower's representations, warranties, and agreements, as set
forth in the Existing Loan Documents. Except as expressly modified pursuant to
this Loan Modification Agreement, the terms of the Existing Loan Documents
remain unchanged and in full force and effect. Bank's agreement to
modifications to the existing indebtedness pursuant to this Loan Modification
Agreement in no way shall obligate Bank to make any future modifications to the
indebtedness. Nothing in this Loan Modification Agreement shall constitute a
satisfaction of the indebtedness. It is the intention of Bank and Borrower to
retain as liable parties all makers and endorsers of Existing Loan Documents,
unless the party is expressly released by Bank in writing. No maker, endorser,
or guarantor will be released by virtue of this Loan Modification Agreement.
The terms of this paragraph apply not only to this Loan Modification Agreement,
but also to all subsequent loan modification agreements.

8.   CONDITIONS. The effectiveness of this Loan Modification Agreement is
conditioned upon Borrower's payment of the Revolving Loan Fee and the Equipment
Advance Fee.

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     This Loan Modification Agreement is executed as of the date first written
above.

BORROWER:                                      BANK:

YIELDUP INTERNATIONAL CORPORATION              SILICON VALLEY BANK

By: /s/ ARHAY K. BHUSHAN                       By: /s/ MICHAEL J. ROSE       
    -----------------------------                  ---------------------------

Name: ARHAY K. BHUSHAN                         Name: MICHAEL J. ROSE         
      ---------------------------                    -------------------------

Title:  Exec. V.P. & CFO                       Title: Vice President          
      ---------------------------                     ------------------------


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