LONG-TERM RETENTION AGREEMENT - CASH

<PAGE>

                                                                 Exhibit 10.18.2

                      LONG-TERM RETENTION AGREEMENT - CASH

     This Long-Term Retention Agreement-Cash (the "Agreement") is made and
entered into effective as of September 21, 2004 (the "Grant Date") by and
between Western Digital Corporation, a Delaware corporation, and John F. Coyne
(the "Executive") dated as of the Grant Date.

                                   WITNESSETH:

     WHEREAS, the Executive is employed by Western Digital Technologies, Inc., a
subsidiary of the Company, in a key position and the Company desires the
Executive to remain in such service;

     WHEREAS, to give the Executive added incentive to advance the interests of
the Company, the Company wishes to grant the Executive a cash award under the
terms and conditions established by Company;

     NOW, THEREFORE, in consideration of these premises, the parties agree that
the following shall constitute the agreement between the Company and the
Executive:

     1. DEFINITIONS.

     As used herein, the following terms shall have the meanings ascribed
thereto below:

          (a) "ACCOUNT" means a bookkeeping account maintained by the Company
for this Award to track vesting and value pursuant to Section 4.

          (b) "ADMINISTRATOR" means the Committee.

          (c) "BOARD" means the Board of Directors of the Company.

          (d) "CASH AWARD" means the commitment of the Company to make payments
in cash under this Agreement to the Executive in amounts determined in
accordance with Section 4.

          (e) "CHANGE OF CONTROL" has the meaning set forth in the Company's
Change of Control Severance Plan.

          (f) "CHANGE OF CONTROL SEVERANCE PLAN" means the Company's Amended and
Restated Change of Control Severance Plan.

          (g) "COMMITTEE" means the Compensation Committee of the Board
consisting solely of two (2) or more Non-employee Directors.

          (h) "COMPANY" means Western Digital Corporation, a Delaware
corporation, and its subsidiaries and affiliates, unless the context otherwise
requires.


<PAGE>

          (i) "DEFERRED COMPENSATION PLAN" means the Company's Amended and
Restated Deferred Compensation Plan, as amended from time to time, or any
successor deferred compensation plan adopted by the Company.

          (j) "NON-EMPLOYEE DIRECTOR" means a director who is both a
"non-employee director" as defined in Rule 16b-3 under the Securities Exchange
Act of 1934, as amended, and an "outside director" within the meaning of Section
162(m) of the Internal Revenue Code of 1986, as amended.

          (k) "PAYMENT AMOUNT" has the meaning set forth in Section 4.5.

          (l) "SUB-ACCOUNT" means a First Sub-Account, Second Sub-Account, or
Third Sub-Account making up a portion of an Account as described in Section 3.1.

     2. AWARD.

          2.1 Award Terms. The Company hereby grants to the Executive a Cash
Award of $300,000.00, subject to vesting and termination as set forth in Section
4.

          2.2 Continued Employment. The grant of a Cash Award to the Executive
pursuant to this Agreement does not give the Executive any right to be retained
in the employ of the Company; and the right and power of the Company to dismiss
or discharge the Executive, with or without cause, for any reason, is
specifically reserved. Nothing in this Agreement is intended to alter the
at-will nature of Executive's employment.

          2.3 No Property Rights. The grant of a Cash Award to the Executive
pursuant to this Agreement shall not be deemed the grant of a property interest
in any assets of the Company. The Cash Award evidences only a general obligation
of the Company to comply with the terms and conditions of the Agreement and make
payments in accordance with the Agreement from the assets of the Company that
are available for the satisfaction of obligations to creditors. The Company
shall not segregate any assets in respect of the Cash Award or the Executive's
Account. The rights of the Executive to benefits under this Agreement shall be
solely those of a general, unsecured creditor of the Company.

          2.4 No Rights as a Stockholder. The Executive shall have no dividend,
voting, or any other rights as a stockholder with respect to any Account.

          2.5 Reorganization. This Cash Award shall not affect the right of the
Company to reclassify, recapitalize or otherwise change its capital or debt
structure or to merge, consolidate, convey any or all of its assets, dissolve,
liquidate, windup or otherwise reorganize.

     3. CREDITS TO ACCOUNTS.

          3.1 Credits. The Company shall establish an Account for the Executive
with respect to the Cash Award. An amount equal to the Cash Award g