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                                 PROMISSORY NOTE

$5,000,000.00                                                     July 22, 1999


         For Value received, MICHAEL D. CAPELLAS ("Maker"), promises to pay
to the order of COMPAQ COMPUTER CORPORATION, a Delaware Corporation
("Payee"), at 20555 State Highway 249, Houston, Texas 77070 (or at such other
place which may be hereafter designated by written notice to the Maker from
the Payee) in lawful money of the United States of America:

                  (a)      the principal sum of Five Million and 00/100 Dollars
                           ($5,000,000.00),

                  (b)      interest from the date of this Note until the
                           maturity (howsoever such maturity may be brought
                           about) upon the unpaid principal balance at the rate
                           of 5.67% per annum, compounded monthly, and

                  (c)      interest on past due principal and interest at the
                           rate of eighteen percent (18%) per annum.

         This Note shall be payable in full in a single installment of
principal and accrued interest on the date that is the earlier of (i) July
22, 2004 and (ii) one hundred twenty (120) days following the termination of
employment of the Maker with the Payee.

         The Maker shall have the right and privilege of prepaying, without
notice or penalty, at any time and from time to time, all or any part of this
Note. All prepayments shall be applied first to accrued interest and then to
installments of principal.

         In the event of default in the payment of either principal or
interest hereon, in whole or in part, or in the performance of any agreement
or covenant contained in any instrument securing the payment hereof or
executed in connection herewith, the owner hereof shall have the right and
option, without notice or demand, to declare the principal and accrued
interest on this Note at once due and payable, and to foreclose or require
foreclosure of any and all liens or security interests securing the payment
hereof. Failure to exercise such right upon any default shall not constitute
a waiver of the right to exercise it in the event of any subsequent default.
If this Note is placed in the hands of an attorney for collection, or if
collected through the probate court, bankruptcy court, or by any other legal
or judicial proceedings, the undersigned agrees and is to pay reasonable
costs and expenses of collection, including, but not limited to, reasonable
attorney's fees and court costs.

         Each Maker, co-maker, surety, guarantor, endorser or other party
liable for the payment of any sums of money payable on this Note severally
waive presentment, notice of dishonor, notice of intent to accelerate
maturity, notice of acceleration of maturity, protest and notice of protest
and nonpayment, bringing of suit, and diligence in taking any action to
collect sums owing hereunder, and agree that their liability on this Note
shall not be affected by any release or change in any security for the
payment of this Note.

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         It is the intention of Maker and Payee to conform strictly to
applicable usury laws. Accordingly, if the transactions contemplated hereby
would be usurious under applicable law (including the laws of the State of
Texas and the laws of the United States of America), then, in that event,
notwithstanding anything to the contrary in any agreement entered into in
connection with or as security for this Note, it is agreed as follows: (i)
the aggregate of all consideration which constitutes interest under
applicable law that is taken, reserved, contracted for, charged or received
under this Note or under any of the other aforesaid agreements or otherwise
in connection with this Note shall under no circumstances exceed the maximum
amount of interest allowed by applicable law, and any excess shall be
credited on the Note by the holder thereof (or, if this Note shall have been
paid in full, refunded to the Maker); and (ii) in the event that maturity of
this Note is accelerated by reason of an election by the holder thereof
resulting from any default hereunder or otherwise, or in the event of any
required or permitted prepayment, then such consideration that constitutes
interest may never include more than the maximum amount allowed by applicable
law, and excess interest, if any, provided for in this Note or otherwise
shall be canceled automatically as of the date of such acceleration or
prepayment and, if theretofore prepaid, shall be credited on this Note (or if
this Note shall have been paid in full, refunded to the Maker).

         This Note is secured by a Security Agreement effective as of the
date hereof, covering certain common stock owned by Maker, and is entitled to
the benefits set forth therein.

                                       ________________________________________
                                       MICHAEL D. CAPELLAS



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