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                                                                   EXHIBIT 10.20

                 THIRD AMENDMENT TO LOAN AND SECURITY AGREEMENT,
                               WAIVER AND CONSENT


         THIS THIRD AMENDMENT TO LOAN AND SECURITY AGREEMENT, WAIVER AND CONSENT
(this "Amendment") is made and entered into as of August 22, 2001 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, as amended by that certain First
Amendment to Loan and Security Agreement, dated as of September 29, 2000 and
that certain Second Amendment to Loan and Security Agreement dated as of
February 7, 2001 (as amended, 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 9.15 of the Agreement. Effective as
of the date hereof, Section 9.15 of the Agreement is hereby amended and restated
to read in its entirety as follows:

                  "9.15 Tangible Net Worth. Borrower shall maintain Tangible Net
         Worth of not less than the amounts set forth below as of the end of the
         corresponding quarters set forth below, provided, however, that for the
         purposes of this Section, non-cash write-offs (excluding the write-off
         of current and long term deferred tax assets) taken in accordance with
         GAAP in fiscal years 2000 and 2001 shall be excluded form the
         calculation of Tangible Net Worth:


Third Amendment to Loan and Security Agreement
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<Table>
<Caption>
                                                      Minimum Tangible
                            Period                        Net Worth
                            ------                    ----------------
<S>                                                   <C>
                July 1, 2001 through September           $11,550,000
                30, 2001
                October 1, 2001 through                  $ 8,350,000
                December 31, 2001
                January 1, 2002 through March            $ 8,350,000
                31, 2002
                April 1, 2002 through June 30,           $ 9,000,000
                2002
                July 1, 2002 through September           $10,300,000
                30, 2002
                October 1, 2002 through                  $12,300,000
                December 31, 2002
                January 1, 2003 through March            $ 9,000,000
                31, 2003
</Table>

                                   ARTICLE III
                              CONDITIONS PRECEDENT

         Section 3.01. Conditions Precedent to Amendment. 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 the following documents, duly
         executed by the parties thereto:

                  (i) this Amendment;

                  (ii) a Company General Certificate dated as of the date of
         this Amendment, in form and substance satisfactory to Lender, certified
         by the Secretary of Borrower certifying among other things, (x) that
         Borrower's Board of Directors has met and has adopted, approved,
         consented to and ratified resolutions which authorize the execution,
         delivery and performance by Borrower of this Amendment and all such
         other loan documents to which it is or is to be a party, and (y) the
         names of the officers of such Borrower authorized to sign this
         Amendment and each of such other loan documents to which it is or
         is to be a party

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Third Amendment to Loan and Security Agreement
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         hereunder (including the certificates contemplated herein) together
         with specimen signatures of such officers;

         (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) Except as waived hereby, no default shall have occurred under the
Agreement or any of the other Loan Documents and be continuing, unless such
default has been specifically waived in writing by Lender;

         (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;

         (e) The financing transaction between Borrower and certain lenders (the
"Bridge Lenders") who are also beneficial owners of capital stock of Ecrix
Corporation, a Delaware corporation ("Ecrix"), shall have been consummated
pursuant to the terms of the Loan and Security Agreement, dated as of even date
herewith (the "Bridge Loan Agreement"), a copy of which is attached hereto (the
"Bridge Loan") and Borrower shall have furnished Lender a copy of a fully
executed counterpart of the Bridge Loan Agreement and the documents and
instruments executed in connection with the Bridge Loan;

         (f) Lender shall have received from Borrower a closing fee for this
Amendment in the amount of $50,000, which fee shall be deemed fully earned and
nonrefundable upon receipt thereof; and

         (g) The Bridge Lenders and Lender shall have executed a Subordination
and Intercreditor Agreement of even date herewith (the "Intercreditor
Agreement") with respect to certain assets of Borrower pursuant to terms and
conditions satisfactory to Lender in its sole discretion.

         Section 3.02. Conditions Precedent to Merger.

         (a) As soon as available, Borrower shall deliver to Lender a copy of
the executed Merger Agreement and related documents (as defined below) and the
Intercreditor Agreement;

         (b) The representations and warranties of Borrower 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") and in the
Merger Agreement and related documents, shall be true and correct in all
material respects as of the date hereof as if made on the date hereof;

         (c) No default shall have occurred under the Merger Agreement or any of
the documents related to the Merger Agreement, and be continuing, unless such
default has been specifically



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Third Amendment to Loan and Security Agreement
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waived in writing by the parties thereto and each the conditions precedent
thereto shall have been met to the reasonable satisfaction of the parties
thereto and the Lender;

         (d) All corporate proceedings taken in connection with the transactions
contemplated by the Merger Agreement and the related documents shall be
satisfactory to Lender and its legal counsel, Patton Boggs LLP;

         (e) Borrower shall have made such changes and amendments to the
Financing Agreements as Lender may reasonably require to reflect final
consummation and structure of the Merger including but not limited to changes to
Section 9.12 with respect to limitations on distributions, transactions with
affiliates, cash flow and investments in subsidiaries, as Lender may reasonable
request; and

         (e) Lender shall have received a certificate regarding the solvency of
Borrower after giving effect to the Merger, in form and substance satisfactory
to Lender, executed by the chief financial officer of Borrower.


                                   ARTICLE IV
                           LIMITED WAIVER AND CONSENT

         SECTION 4.01. REQUESTED WAIVER. Borrower has requested (a) permission
from the Lender (i)for Borrower to (w) execute, deliver and perform its
obligations under the Bridge Loan Agreement; (x) issue and perform its
obligations pursuant to 12% Subordinated Secured Convertible Notes to Bridge
Lender (subject to the terms of the Intercreditor Agreement); (y) grant to
Bridge Lenders a second lien security interest in the assets of Borrower,
subject to the terms and conditions of the Intercreditor Agreement; and (z) use
the proceeds of the Bridge Loan solely for general working capital purposes and
to pay off certain trade creditors of Borrower (all of the foregoing hereinafter
referred to as the "Loan Transaction") and (ii) to enter into, deliver and
perform its obligations under an Agreement and Plan of Merger (the "Merger
Agreement") dated as of even date herewith for the merger of a subsidiary of
Borrower with and into Ecrix Corporation ("Ecrix") substantially on the terms of
the Merger Agreement which has been previously supplied to Lender (the
"Merger"), and (iii) for Borrower to (x) issue its Series H Convertible
Preferred Stock (the "Series H Preferred") to the Bridge Lenders and certain
other investors having the rights and preferences set forth in the form of
Certificate of Designations for the Series H Preferred, a copy of which is
attached hereto and (y) use the proceeds from the sale of the Series H Preferred
solely for general working capital purposes and to pay off certain trade
creditors of Borrower (all of the foregoing hereinafter referred to as the
"Preferred Stock Transaction"), (b) that the Lender waive the covenants embodied
in the Loan Agreement to the extent such covenants would be deemed violated due
to execution, delivery and performance by Borrower of the Bridge Loan Agreement
or the Merger Agreement, and the consummation of Merger and the Preferred Stock
Transaction, and (c) waive any default or Event of Default arising as a result
of Borrower's failure to maintain Tangible Net Worth as required pursuant to
Section 9.15 of the Agreement for each of the quarters ended March 31, 2001 and
June 30, 2001.


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         SECTION 4.02 WAIVER AND CONSENT. Subject to the terms and conditions
set forth herein in Article III, and in reliance on the representations and
warranties of Borrower made herein, Lender hereby:

         (a) waives the covenants embodied in the Loan Agreement to the extent
such covenants would be deemed violated solely due to the execution, delivery
and performance by Borrower of the Bridge Loan Agreement or the Merger
Agreement, and the consummation of the Merger and the Preferred Stock
Transaction, provided, that Borrower shall not borrow funds under the Loan
Agreement to pay any type of "break-up" or similar fee required by the Merger
Agreement; and

         (b) waives any default or Event of Default as a result of Borrower's
failure to maintain Tangible Net Worth as required pursuant to Section 9.15 of
the Agreement for each of the quarters ended March 31, 2001 and June 30, 2001.


                                   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 6.02. 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 in all material respects on and as of the date hereof as though
made on and as of the date hereof, (iii) other than as waived by Lender by this
Amendment or prior documentation, Borrower is in compliance in all material
respects 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 VII
                                  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.



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         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, 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.


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         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 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, Colorado 80229





Third Amendment to Loan and Security Agreement