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                                                                 EXHIBIT 10.22.1

                           SECOND AMENDMENT TO LEASE

I.    PARTIES AND DATE.

      This Second Amendment to Lease dated January 6, 1999, is by and between
THE IRVINE COMPANY ("Landlord"), and WESTERN DIGITAL CORPORATION, a Delaware
corporation ("Tenant").

II.   RECITALS.

      On January 13, 1988, Landlord and Tenant entered into an office space
lease for the office building located at 8105 Irvine Center Drive, Irvine,
California, and related parking and landscape areas more particularly described
therein, which lease was subsequently amended by a First Amendment to Lease
dated May 18, 1990 (as amended, the "Lease").

      Landlord and Tenant each desire to modify the Lease to extend the Lease
Term, adjust the Basic Rent, and make such other modifications as are set forth
in "III. MODIFICATIONS" next below.

III.  MODIFICATIONS.

      A.    Lease Term. Notwithstanding any contrary provision in the Lease,
unless sooner terminated for default or breach of the terms, covenants or
conditions of the Lease, Landlord and Tenant hereby agree to extend the Term of
the Lease to expire at midnight on December 31, 2000.

      B.    Basic Rent. Notwithstanding any contrary provision in the Lease,
Landlord and Tenant hereby agree that the Basic Rent payable by Tenant during
the six (6) month period commencing July 1, 2000 shall be Six Hundred
Eighty-Seven Thousand Two Hundred Twelve Dollars ($687,212.00) per month, based
on $1.92 per rentable square foot.

      C.    Right to Extend the Lease Term. Section 3.1 of the Lease is hereby
amended by deleting Subparagraphs (b), (c), (d), (e), and (f) therefrom. In
lieu thereof, Landlord hereby agrees that provided Tenant is not in default
under any provision of the Lease at the time of exercise of the extension right
granted herein, and provided further that Tenant has not assigned or sublet any
of its interest in the Lease, Tenant may extend the Term of the Lease for one
(1) additional period of six (6) months (the "Extension Period"). Tenant shall
exercise its right to extend the Term by and only by (i) delivering to Landlord
prior to December 31, 1999, Tenant's written notice of its commitment to extend
(the "Commitment Notice"); and (ii) returning to Landlord, within fifteen (15)
days after receipt, an executed amendment to this Lease (to be prepared by
Landlord upon receipt of the Commitment Notice). The Basic Rent payable under
the Lease during the Extension Period shall be at the same rate set forth in
Paragraph III.B above. If Tenant fails to timely comply with any of the
provisions of this paragraph, Tenant's right to extend the Term shall be
extinguished and the Lease shall automatically terminate as of midnight on
December 31, 2000, without any extension and without any liability to Landlord.
Any attempt to assign or transfer any right or interest created by this
paragraph shall be void from its inception. Tenant shall have no other right to
extend the Term beyond the Extension Period described in this paragraph. Unless
agreed to in a writing signed by Landlord and Tenant, any extension of the
Term, whether created by an amendment to the Lease or by a holdover of the
Premises by Tenant, or otherwise, shall be deemed a part of, and not in
addition to, any duly exercised extension period permitted by this paragraph.

      D.    Parking. Landlord hereby agrees that Tenant's current parking
privileges shall remain unchanged during the six (6) month period commencing
July 1, 2000,and if applicable, during the Extension Period. Landlord further
agrees that Tenant's allotted parking spaces shall


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be provided to Tenant free of charge during the aforementioned twelve (12)
month period. Thereafter, the stall charge payable by Tenant shall be at
Landlord's scheduled parking rates from time to time.

     E.   Parking Rights Agreement. Landlord and Tenant hereby agree that the
separate "Parking Rights" agreement between the parties dated July 6, 1998
shall remain in full force and effect during the six (6) month period
commencing July 1, 2000, and if applicable, during the Extension Period.

IV.  GENERAL.

     A.   Effect of Amendments. The Lease shall remain in full force and effect
except to the extent that it is modified by this Amendment.

     B.   Entire Agreement. This Amendment embodies the entire understanding
between Landlord and Tenant with respect to the modifications set forth in
"III. MODIFICATIONS" above and can be changed only by a writing signed by
Landlord and Tenant.

     C.   Counterparts. If this Amendment is executed in counterparts, each is
hereby declared to be an original; all, however, shall constitute but one and
the same amendment. In any action or proceeding, any photographic, photostatic,
or other copy of this Amendment may be introduced into evidence without
foundation.

     D.   Defined Terms. All words commencing with initial capital letters in
this Amendment and defined in the Lease shall have the same meaning in this
Amendment as in the Lease, unless they are otherwise defined in this Amendment.

     E.   Corporate and Partnership Authority. If Tenant is a corporation or
partnership, or is comprised of either or both of them, each individual
executing this Amendment for the corporation or partnership represents that he
or she is duly authorized to execute and deliver this Amendment on behalf of
the corporation or partnership and that this Amendment is binding upon the
corporation or partnership in accordance with its terms.

     F.   Attorneys' Fees. The provisions of the Lease respecting payment of
attorneys' fees shall also apply to this Amendment.

V.   EXECUTION.

     Landlord and Tenant executed this Amendment on the date as set forth in
"I. PARTIES AND DATE," above.

LANDLORD:                               TENANT:

THE IRVINE COMPANY                      WESTERN DIGITAL CORPORATION


By: /s/ WILLIAM R. HALFORD              By /s/ [SIGNATURE ILLEGIBLE] 1/4/00
   ------------------------------         --------------------------------
   William R. Halford, President
   Irvine Office Company                Title  CFO
   a division of the Irvine Company           ----------------------------


By /s/ RICHARD G. SIM                   By /s/ [SIGNATURE ILLEGIBLE]
   ------------------------------         --------------------------------
   Richard G. Sim,
   Executive Vice President             Title V.P. Law & Secretary
                                              ----------------------------


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