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                                                                   EXHIBIT 10.18

                 FIRST AMENDMENT TO LOAN AND SECURITY AGREEMENT


         THIS FIRST AMENDMENT TO LOAN AND SECURITY AGREEMENT (this "Amendment")
is made and entered into as of the 29th day of September, 2000 by and among
CONGRESS FINANCIAL CORPORATION (SOUTHWEST), a Texas corporation ("Lender") and
EXABYTE CORPORATION, a Delaware corporation ("Borrower").

         WHEREAS, Borrower and Lender are parties to that certain Loan and
Security Agreement dated as of May 16, 2000 (the "Agreement");

         WHEREAS, Borrower and Lender desire to amend the Agreement in the
manner provided below;

         NOW, THEREFORE, for good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the parties hereto hereby agree as
follows:

                                    ARTICLE I
                                   DEFINITIONS

         Section 1.01. Definitions. Capitalized terms used in this Amendment, to
the extent not otherwise defined herein, shall have the same meaning as in the
Agreement, as amended hereby.

                                   ARTICLE II
                                   AMENDMENTS


         Section 2.01. Amendment to Section 9.10(c) of the Agreement. Effective
as of the date hereof, Section 9.10(c) of the Agreement is hereby amended and
restated to read in its entirety as follows:

                  "(c) loans or advances to Borrower's subsidiaries (other than
         subsidiaries that are Obligors) not exceeding the sum of the amounts
         set forth on Schedule 9.10 plus $1,000,000 in the aggregate outstanding
         at any time."

         Section 2.02. Amendment to Schedule 9.10 of the Agreement. Effective as
of the date hereof, Schedule 9.10 of the Agreement is hereby amended and
restated to read in its entirety as follows:



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                                 "Schedule 9.10

                     Existing Loans, Advances and Guarantees



                  9.10(c): CreekPath Systems, Inc.               $1,152,125
                           Exabyte Europe                        $  361,168
                           Exabyte Magnetics                     $1,674,580
                           Exabyte Singapore                     $1,216,569
                           Exabyte Canada                        $  401,152

                  9.10(d)  None."

                                   ARTICLE III
                              CONDITIONS PRECEDENT

         Section 3.01. Conditions. The effectiveness of this Amendment is
subject to the satisfaction of the following conditions precedent, unless
specifically waived by Lender:

                  (a) Lender shall have received (i) this Amendment, duly
         executed by Borrower and (ii) such additional documents, instruments
         and information as Lender or its legal counsel may request;

                  (b) The representations and warranties contained herein, in
         the Agreement, as amended hereby, and/or in the other documents and
         agreements relating hereto or thereto (hereinafter individually
         referred to as a "Loan Document" and collectively referred to as the
         "Loan Documents") shall be true and correct as of the date hereof as
         if made on the date hereof;

                  (c) No default shall have occurred under the Agreement and be
         continuing and no default shall exist under the Agreement unless such
         default has been specifically waived in writing by Lender; and

                  (d) All corporate proceedings taken in connection with the
         transactions contemplated by this Amendment and all documents,
         instruments and other legal matters incident thereto shall be
         satisfactory to Lender and its legal counsel, Patton Boggs LLP.

                                   ARTICLE IV
                                    NO WAIVER

         Except as specifically provided in this Amendment, nothing contained in
this Amendment shall be construed as a waiver by Lender of any covenant or
provision of the Agreement, the other Loan Documents, this Amendment, or of any
other contract or instrument between Borrower and Lender, and the failure of
Lender at any time or times hereafter to require strict performance by Borrower
of any provision thereof shall not





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waive, affect or diminish any right of Lender to thereafter demand strict
compliance therewith. Lender hereby reserves all rights granted under the
Agreement, the other Loan Documents, this Amendment and any other contract or
instrument between Borrower and Lender.

                                    ARTICLE V
                  RATIFICATIONS, REPRESENTATIONS AND WARRANTIES

         Section 5.01 Ratifications. The terms and provisions set forth in this
Amendment shall modify and supersede all inconsistent terms and provisions set
forth in the Agreement and except as expressly modified and superseded by this
Amendment, the terms and provisions of the Agreement are ratified and confirmed
and shall continue in full force and effect.

         Section 5.02 Representations and Warranties. Borrower hereby represents
and warrants to Lender that (i) the execution, delivery and performance of this
Amendment and any and all other Loan Documents executed and/or delivered in
connection herewith have been authorized by all requisite corporate action on
the part of Borrower and will not violate the Certificate of Incorporation or
Bylaws of Borrower, (ii) the representations and warranties contained in the
Agreement, as amended hereby, and any other Loan Document are true and correct
on and as of the date hereof as though made on and as of the date hereof, (iii)
Borrower is in full compliance with all covenants and agreements contained in
the Agreement, as amended hereby, and (iv) Borrower has not amended its
Certificate of Incorporation or Bylaws since May 16, 2000.

                                   ARTICLE VI
                                  MISCELLANEOUS


         Section 6.01. Survival of Representations and Warranties. All
representations and warranties made in the Agreement or any other document or
documents relating thereto, including, without limitation, any Loan Document
furnished in connection with this Amendment, shall survive the execution and
delivery of this Amendment and the other Loan Documents, and no investigation by
Lender or any closing shall affect the representations and warranties or the
right of Lender to rely upon them.

         Section 6.02. Reference to Agreement. Each of the Loan Documents,
including the Agreement and any and all other agreements, documents or
instruments now or hereafter executed and delivered pursuant to the terms hereof
or pursuant to the terms of the Agreement as amended hereby, are hereby amended
so that any reference in such Loan Documents to the Agreement shall mean a
reference to the Agreement as amended hereby.

         Section 6.03. Expenses of Lender. As provided in the Agreement,
Borrower agrees to pay on demand all reasonable costs and expenses incurred by
Lender in connection with the preparation, negotiation and execution of this
Amendment and the other Loan Documents executed pursuant hereto and any and all
amendments,



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modifications, and supplements thereto, including without limitation the
reasonable costs and fees of Lender's legal counsel, and all reasonable costs
and expenses incurred by Lender in connection with the enforcement or
preservation of any rights under the Agreement, as amended hereby, or any other
Loan Document, including without limitation the reasonable costs and fees of
Lender's legal counsel.

         Section 6.04. Severability. Any provision of this Amendment held by a
court of competent jurisdiction to be invalid or unenforceable shall not impair
or invalidate the remainder of this Amendment and the effect thereof shall be
confined to the provision so held to be invalid or unenforceable. Furthermore,
in lieu of each such invalid or unenforceable provision there shall be added
automatically as a part of this Amendment a valid and enforceable provision that
comes closest to expressing the intention of such invalid or unenforceable
provision.

         SECTION 6.05. APPLICABLE LAW. THIS AMENDMENT AND ALL OTHER LOAN
DOCUMENTS EXECUTED PURSUANT HERETO SHALL BE DEEMED TO HAVE BEEN MADE AND TO BE
PERFORMABLE IN DALLAS, TEXAS AND SHALL BE GOVERNED BY AND CONSTRUED IN
ACCORDANCE WITH THE LAWS OF THE STATE OF TEXAS.

         Section 6.06. Successors and Assigns. This Amendment is binding upon
and shall inure to the benefit of Lender and Borrower and their respective
successors and assigns, except Borrower may not assign or transfer any of its
rights or obligations hereunder without the prior written consent of Lender.

         Section 6.07. Counterparts. This Amendment may be executed in one or
more counterparts, each of which when so executed shall be deemed to be an
original, but all of which when taken together shall constitute one and the same
instrument.

         Section 6.08. Effect of Waiver. No consent or waiver, express or
implied, by Lender to or for any breach of or deviation from any covenant or
condition of the Agreement shall be deemed a consent or waiver to or of any
other breach of the same or any other covenant, condition or duty.

         Section 6.09. Headings. The headings, captions, and arrangements used
in this Amendment are for convenience only and shall not affect the
interpretation of this Amendment.

         SECTION 6.10. NO ORAL AGREEMENTS. THE AGREEMENT AND THE OTHER LOAN
DOCUMENTS REPRESENT THE FINAL AGREEMENT BETWEEN THE PARTIES AND MAY NOT BE
CONTRADICTED BY EVIDENCE OF PRIOR, CONTEMPORANEOUS OR SUBSEQUENT ORAL AGREEMENTS
OF THE PARTIES. THERE ARE NO UNWRITTEN ORAL AGREEMENTS BETWEEN THE PARTIES.

         SECTION 6.11. RELEASE. BORROWER HEREBY ACKNOWLEDGES THAT IT HAS NO
DEFENSE, COUNTERCLAIM, OFFSET, CROSS-COMPLAINT, CLAIM OR DEMAND OF ANY KIND OR
NATURE




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WHATSOEVER THAT CAN BE ASSERTED TO REDUCE OR ELIMINATE ALL OR ANY PART OF ITS
LIABILITY TO REPAY THE "OBLIGATIONS" OR TO SEEK AFFIRMATIVE RELIEF OR DAMAGES OF
ANY KIND OR NATURE FROM LENDER. BORROWER HEREBY VOLUNTARILY AND KNOWINGLY
RELEASES AND FOREVER DISCHARGES LENDER, ITS PREDECESSORS, AGENTS, EMPLOYEES,
SUCCESSORS AND ASSIGNS, FROM ALL POSSIBLE CLAIMS, DEMANDS, ACTIONS, CAUSES OF
ACTION, DAMAGES, COSTS, EXPENSES, AND LIABILITIES WHATSOEVER, KNOWN OR UNKNOWN,
ANTICIPATED OR UNANTICIPATED, SUSPECTED OR UNSUSPECTED, FIXED, CONTINGENT, OR
CONDITIONAL, AT LAW OR IN EQUITY, ORIGINATING IN WHOLE OR IN PART ON OR BEFORE
THE DATE THIS AMENDMENT IS EXECUTED, WHICH THE BORROWER MAY NOW OR HEREAFTER
HAVE AGAINST LENDER, ITS PREDECESSORS, AGENTS, EMPLOYEES, SUCCESSORS AND
ASSIGNS, IF ANY, AND IRRESPECTIVE OF WHETHER ANY SUCH CLAIMS ARISE OUT OF
CONTRACT, TORT, VIOLATION OF LAW OR REGULATIONS, OR OTHERWISE, AND ARISING FROM
ANY "LOANS", INCLUDING, WITHOUT LIMITATION, ANY CONTRACTING FOR, CHARGING,
TAKING, RESERVING, COLLECTING OR RECEIVING INTEREST IN EXCESS OF THE HIGHEST
LAWFUL RATE APPLICABLE, THE EXERCISE OF ANY RIGHTS AND REMEDIES UNDER THE LOAN
AGREEMENT OR OTHER AGREEMENTS, AND NEGOTIATION FOR AND EXECUTION OF THIS
AMENDMENT.



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                  IN WITNESS WHEREOF, this Amendment has been duly executed by
Borrower and Lender to be effective as of the date first above written.



     LENDER:                                BORROWER:
     ------                                 --------

     CONGRESS FINANCIAL CORPORATION         EXABYTE CORPORATION
     (SOUTHWEST)



     By:                                    By:
        --------------------------------       --------------------------------
     Name:                                  Name:
          ------------------------------         ------------------------------
     Title:                                 Title:
           -----------------------------          -----------------------------

     ADDRESS:                               CHIEF EXECUTIVE OFFICE:

     1201 Main Street, Suite 1625           1685 38th Street
     Dallas, Texas  75202                   Boulder, CO  80229