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                                                                   EXHIBIT 10.69

                                                               EXECUTION VERSION

                      FIFTH AMENDMENT TO CREDIT AGREEMENT
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     1.   Reference is made to that certain Credit Agreement dated as of June 6,
1997 (the "Credit Agreement"), as amended by that certain First Amendment to
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Credit Agreement dated as of June 26, 1998, as further amended by that certain
Second Amendment to Credit Agreement dated as of December 18, 1998, as further
amended by that certain Third Amendment to Credit Agreement dated as of August
31, 1999, and as further amended by that certain Fourth Amendment to Credit
Agreement dated as of November 8, 1999, by and among Quantum Corporation, a
Delaware corporation (the "Borrower"), each of the financial institutions listed
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in Schedule I to the Credit Agreement (individually, a "Bank" and, collectively,
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the "Banks"), Canadian Imperial Bank of Commerce, as administrative agent for
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the Banks (in such capacity, "Administrative Agent"), ABN AMRO Bank, N.V
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("ABN"), and CIBC Inc., as co-arrangers for the Banks, ABN, as syndication agent
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for the Banks, Bank of America, N.A. (formerly known as Bank of America National
Trust and Savings Association), as documentation agent for the Banks, and
BankBoston, N.A., The Bank of Nova Scotia, Fleet National Bank and The
Industrial Bank of Japan, Limited, as co-agents for the Banks (as amended, the
"Credit Agreement").
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     2.   The Banks executing this Amendment constituting Majority Banks hereby
agree that, subject to the satisfaction of the conditions set forth in Paragraph
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3 below, the Credit Agreement is hereby amended as follows:
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          (a)  Subparagraph 5.02(f) of the Credit Agreement is hereby amended by
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     changing clause (iv) thereof to read in its entirety as follows:
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               (iv) Borrower may purchase Equity Securities pursuant to stock
          repurchase programs, provided that the aggregate payments under such
          programs do not exceed (A) during fiscal year 1999, twenty-three
          percent (23%) of Tangible Net Worth as determined as of the fiscal
          quarter ending March 31, 1998, (B) during fiscal year 2000, twenty
          percent (20%) of Tangible Net Worth as determined as of the fiscal
          quarter ending June 27, 1999 plus an additional one hundred twenty
          five million dollars ($125,000,000), and (C) during all other fiscal
          years until the Maturity Date, ten percent (10%) of Tangible Net Worth
          as determined as of the fiscal quarter immediately preceding the date
          of determination;

          (b)  Clause (ii) of Subparagraph 5.02(l) is hereby amended by (i)
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     deleting the "." appearing at the end of Subclause (H) thereof and
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     replacing it with a ";", and (ii) adding the following immediately after
     Subclause (H):
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                                     minus
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               (I)  An amount equal to the aggregate amount paid by Borrower
          during its fiscal year 2000 to repurchase its capital stock as
          permitted pursuant to the phrase "plus an additional one hundred
          twenty five million dollars ($125,000,000)" appearing in Subclause (B)
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          of clause (iv) of Subparagraph 5.02((f).
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     3.   The amendment effected by Paragraph 2 above shall become effective as
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of 5:00 p.m. Pacific Standard Time on January 14, 2000 (the "Effective Date"),
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subject to:  (1) receipt by Orrick, Herrington & Sutcliffe LLP ("OH&S"), counsel
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to Administrative Agent, on or prior to the Effective Date, of a duly executed
copy of this Amendment from Borrower and the Banks constituting the Majority
Banks; and (2) receipt by Administrative Agent on behalf of each individual Bank
that executes this Amendment and delivers an executed copy of this Amendment to
OH&S on or prior to the Effective Date of a non refundable amendment fee payable
to each such Bank in the amount equal to 0.03% of each such Bank's respective
Proportionate Share.

     4.   This Amendment shall be governed by and construed in accordance with
the laws of the State of California without reference to conflicts of law rules.

     IN WITNESS WHEREOF, the undersigned has caused this Amendment to be
executed as of January 14, 2000.


                              QUANTUM CORPORATION


                              By:  /s/ Andrew Kryder
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                              Name:  Andrew Kryder
                              Title: Vice President, Finance & General Counsel