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                                                           Exhibit 4.01

THIS WARRANT AND THE SHARES ISSUABLE HEREUNDER HAVE NOT BEEN REGISTERED UNDER
THE SECURITIES ACT OF 1933, AS AMENDED, AND MAY NOT BE SOLD, PLEDGED, OR
OTHERWISE TRANSFERRED WITHOUT AN EFFECTIVE REGISTRATION THEREOF UNDER SUCH
ACT OR PURSUANT TO RULE 144 OR AN OPINION OF COUNSEL REASONABLY SATISFACTORY
TO THE CORPORATION AND ITS COUNSEL, THAT SUCH REGISTRATION IS NOT REQUIRED.

THIS SECURITY IS SUBJECT TO CERTAIN RESTRICTIONS UPON TRANSFER, INCLUDING BUT
NOT LIMITED TO A RIGHT OF FIRST OFFER ON BEHALF OF THE COMPANY, AS SET FORTH
IN AN AGREEMENT BETWEEN THE COMPANY AND THE STOCKHOLDER, A COPY OF WHICH IS
ON FILE WITH THE SECRETARY OF THE COMPANY.


                            WARRANT TO PURCHASE STOCK

Corporation:                 Adaptec, Inc.
Number of Shares:            696,000
Class of Stock:              Common Stock
Initial Exercise Price:      $62.25 per share
Issue Date:                  January 17, 2000
Expiration Date:             January 16, 2004

         This Warrant certifies that, for good and valuable consideration,
Agilent Technologies, Inc., a Delaware corporation ("HOLDER") is entitled to
purchase from the corporation named above (the "COMPANY"), until 5:00 p.m.
Pacific standard time, on the Expiration Date set forth above, the number of
fully paid and nonassessable shares of the Common Stock (the "SHARES") of the
Company at the initial exercise price per Share (the "WARRANT PRICE"), all as
set forth above and as adjusted pursuant to Section 2 of this Warrant,
subject to the provisions and upon the terms and conditions set forth in this
Warrant.

1.       EXERCISE.

         1.1       VESTING; EXERCISE. As of the Issue Date, this Warrant
shall be exercisable in full by Holder, and Holder may exercise this Warrant,
in whole or in part, by delivering a duly executed Notice of Exercise in
substantially the form attached as EXHIBIT A to the principal office of the
Company. Unless Holder is exercising the conversion right set forth in
Section 1.6, Holder shall also, concurrently with delivery of the Notice of
Exercise, deliver to the Company a check or wire transfer in United States
dollars for the aggregate Warrant Price for the Shares being purchased.

         1.2       DELIVERY OF CERTIFICATE AND NEW WARRANT. Promptly after
Holder exercises this Warrant, the Company shall deliver to Holder
certificates for the Shares acquired and, if this Warrant has not been fully
exercised or converted and has not expired, this Warrant shall automatically
be reduced by the number of Shares as to which the Warrant has been exercised
and remain exercisable for such remaining Shares as to which this Warrant has
not been exercised, and all other terms of the Warrant shall otherwise remain
in full force and effect as so adjusted. Upon final exercise of this Warrant
for any such remaining number of Shares, this Warrant shall be surrendered by
the Holder to the Company for cancellation.

         1.3       REPLACEMENT OF WARRANTS. On receipt of evidence reasonably
satisfactory to the Company of the loss, theft, destruction or mutilation of
this Warrant and, in the case of loss, theft or destruction, on delivery of
an indemnity agreement reasonably satisfactory in form and amount to the
Company or, in the case of mutilation, or surrender and cancellation of this
Warrant, the Company at its expense shall execute and deliver, in lieu of
this Warrant, a new warrant of like tenor.

         1.4       SALE, MERGER, OR CONSOLIDATION OF THE COMPANY.

                   1.4.1.    "ACQUISITION". For the purpose of this Warrant,
"ACQUISITION" means any sale of the Company's stock by the Company's
stockholders in one transaction or series of related transactions or any

                                       1

<PAGE>

reorganization, consolidation or merger of the Company, in any case where,
after the transaction, the holders of the Company's securities before the
transaction beneficially own less than fifty percent (50%) of the outstanding
voting securities of the surviving entity or of its parent corporation if the
surviving entity is a wholly owned subsidiary of such parent corporation.

                   1.4.2     ASSUMPTION OF WARRANT. Upon the closing of any
Acquisition where the consideration for the Acquisition to be received by the
Company's stockholders consists solely of stock or securities of the acquirer
or an entity affiliated with the acquirer, the successor entity shall assume
the obligations of this Warrant, and this Warrant shall be exercisable for
the same securities as would be payable for the Shares issuable upon exercise
of the unexercised portion of this Warrant as if such Shares were outstanding
on the record date for the Acquisition and subsequent closing thereof. The
Warrant Price shall be adjusted accordingly.

                   1.4.3     TERMINATION OF WARRANT. In the case of (a) an
Acquisition where the consideration for the Acquisition to be received by the
Company's stockholders in return for their capital stock of the Company
consists of cash or a combination of cash and other property or (b) the
proposed liquidation and dissolution of the Company, the Company shall give
Holder at least fifteen (15) days advance written notice of such event (the
"COMPANY NOTICE"), which notice shall include the Company's best estimate of
the value of the Shares receivable upon exercise or conversion of this
Warrant and the proposed date upon which such event is expected to occur.
During such notice period, Holder may exercise or convert this Warrant in
accordance with its terms, whether or not exercise or conversion is
contingent upon the happening of such event. Subject to prior exercise or
conversion as provided in the preceding sentence, this Warrant will terminate
at 5:00 p.m. Pacific time on the day prior to the date such event is expected
to occur as set forth in the Company Notice; PROVIDED THAT the event actually
occurs within sixty (60) days after the date it is expected to occur, as such
date was specified in the Company Notice.

         1.5       RESTRICTIONS ON EXERCISE. This Warrant may not be
exercised if the issuance of the Shares upon such exercise would constitute a
violation of any applicable federal or state securities laws or other laws or
regulations. As a condition to the exercise of this Warrant, by the Holder's
execution of the Notice of Exercise attached hereto as EXHIBIT A, the Holder
shall confirm, acknowledge and agree to the representations, warranties and
agreements of the Holder set forth in Section 4 hereof.

         1.6       NET EXERCISE ELECTION. The Holder may elect to convert all
or a portion of this Warrant, without the payment by the Holder of any
additional consideration, by the surrender of this Warrant or such portion of
this Warrant to the Company, with the net exercise election selected in the
Notice of Exercise attached hereto as EXHIBIT A duly executed by the Holder,
into up to the number of Shares that is obtained under the following formula:

                                   X = Y (A-B)
                                       -------
                                           A

where             X =      the number of Shares to be issued to the Holder
                           pursuant to this Section 1.5.

                  Y =      the number of Shares as to which this Warrant is
                           being exercised.

                  A =      the fair market value of one Share, as determined
                           in good faith by the Company's Board of Directors,
                           as at the time the net exercise election is made
                           pursuant to this Section 1.5.

                  B =      the Warrant Price.

         The Company will promptly respond in writing to an inquiry by the
Holder as to the then current fair market value of one Share.

         For purposes of the above calculation, fair market value of one
Share shall be determined by the Company's Board of Directors in good faith;
provided, however, that where there exists a public market for the Company's
Common Stock at the time of such exercise, the fair market value per share
shall be the average of the closing bid and asked prices of the Common Stock
quoted in the Over-The-Counter Market Summary or the last reported sale price
of the Common Stock or the closing price quoted on the Nasdaq National Market
or on any exchange on which the Common Stock is listed, whichever is
applicable, as published in the Western Edition of THE WALL STREET JOURNAL
for the three (3) trading days prior to the date of determination of fair
market value.

                                       2

<PAGE>

2.       ADJUSTMENTS TO THE SHARES.

         2.1       STOCK SPLITS, RECAPITALIZATIONS, ETC. If the Company (i)
pays a dividend in, or makes a distribution of, shares of capital stock or
other securities on its outstanding Common Stock, (ii) subdivides its
outstanding shares of Common Stock in a transaction that increases the amount
of its outstanding shares of Common Stock, or (iii) combines its outstanding
shares of Common Stock in a transaction that decreases the amount of its
outstanding shares of Common Stock, then upon exercise or conversion of this
Warrant, for each Share acquired, Holder shall receive, without cost to
Holder, the total number and kind of securities to which Holder would have
been entitled had Holder owned the Shares of record as of the date such
dividend, distribution, subdivision or combination occurred.

         2.2       CERTAIN CORPORATE TRANSACTIONS. Upon any reclassification,
exchange, substitution, Acquisition of the Company or other similar event
that results in a change of the number and/or class of the securities
issuable upon exercise or conversion of this Warrant other than as provided
in Section 2.1 (a "REORGANIZATION"), Holder shall be entitled to receive,
upon exercise or conversion of this Warrant, the number and kind of
securities and property that Holder would have received for the Shares if
this Warrant had been exercised immediately before such Reorganization. The
Company or its successor shall promptly issue to Holder a new Warrant for
such new securities or other property. The new Warrant shall provide for
adjustments that shall be as nearly equivalent as may be practicable to the
adjustments provided for in this Section 2 including, without limitation,
appropriate adjustments to the Warrant Price and to the number of securities
or property issuable upon exercise or conversion of the new Warrant.

         2.3       ADJUSTMENTS OF WARRANT PRICE. If the outstanding Shares
are combined or consolidated, by reclassification or otherwise, into a lesser
number of shares, the Warrant Price shall be proportionately increased. If
the outstanding Shares are divided by reclassification or otherwise, into a
greater number of shares, the Warrant Price shall be proportionately
decreased.

         2.4       ADJUSTMENT IS CUMULATIVE. The provisions of this Section 2
shall similarly apply to successive, stock dividends, stock splits or
combinations, reclassifications, exchanges, substitutions, or other events.

         2.5       NO IMPAIRMENT. The Company shall not, by amendment of its
Certificate of Incorporation or through a reorganization, transfer of assets,
consolidation, merger, dissolution, issue, or sale of securities or any other
voluntary action, avoid or seek to avoid the observance or performance of any
of the terms to be observed or performed under this Warrant by the Company,
but shall at all times carry out of all the provisions of this Section 2.

         2.6       FRACTIONAL SHARES. No fractional Shares shall be issuable
upon exercise or conversion of the Warrant and the number of Shares to be
issued shall be rounded down to the nearest whole Share. If a fractional
share interest arises upon any exercise or conversion of the Warrant, the
Company shall eliminate such fractional Share interest by paying Holder an
amount by check computed by multiplying the fractional interest by the fair
market value of a full Share.

         2.7       CERTIFICATE AS TO ADJUSTMENTS. Upon each adjustment of the
Warrant Price, the Company at its expense shall compute such adjustment, and
furnish Holder with a certificate of its Chief Financial Officer setting
forth such adjustment and the facts upon which such adjustment is based. The
Company shall, upon written request, furnish Holder a certificate setting
forth the Warrant Price in effect upon the date thereof and the series of
adjustments leading to such Warrant Price.

3.       REPRESENTATIONS AND COVENANTS OF THE COMPANY.

         3.1       REPRESENTATIONS AND WARRANTIES. The Company hereby
represents and warrants to the Holder that all Shares which may be issued
upon the exercise of the purchase right represented by this Warrant, and all
securities, if any, issuable upon conversion of the Shares, shall, upon
issuance, be duly authorized, validly issued, fully paid and nonassessable,
and free of any liens and encumbrances except for restrictions on transfer
provided for herein or under applicable federal and state securities laws.

         3.2       RESERVATION OF THE SHARES. If at any time the number of
shares of Common Stock or other securities issuable upon exercise of this
Warrant shall not be sufficient to effect the exercise of this Warrant, the

                                       3
<PAGE>

Company will take such corporate action as may, in the opinion of its
counsel, be necessary to increase its authorized but unissued shares of
Common Stock or other securities issuable upon exercise of this Warrant as
shall be sufficient for such purpose.

         3.3       NO RIGHTS OR LIABILITIES AS STOCKHOLDER. This Warrant does
not by itself entitle the Holder to any voting rights, cash dividends or
other rights, nor subject Holder to any liabilities, as a stockholder of the
Company. In the absence of affirmative action by the Holder to purchase
Shares by exercise of this Warrant, no provisions of this Warrant, and no
enumeration herein of the rights or privileges of the Holder, shall cause the
Holder to be a stockholder of the company for any purpose.

4.       REPRESENTATIONS OF HOLDER; TRANSFER.

         4.1       REPRESENTATIONS. Holder hereby represents and warrants to
the Company as follows: Holder is a sophisticated investor having such
knowledge and experience in business and investment matters that Holder is
capable of protecting Holder's own interests in connection with the
acquisition, exercise or disposition of this Warrant. Holder is an
"accredited investor" within the meaning of Regulation D promulgated under
the Securities Act of 1933, as amended (the "ACT"). Holder is aware that this
Warrant and the Shares (and the securities issuable, directly or indirectly,
upon conversion of the Shares, if any) (hereinafter, collectively, the
"RESTRICTED SECURITIES") are being, or will be, issued to Holder in reliance
upon Holder's representation in this Section 4 and that such securities are
restricted securities that cannot be publicly sold except in certain
prescribed situations. Holder is aware of the provisions of Rule 144
promulgated under the Act and of the conditions under which sales may be made
thereunder. Holder has received such information about the Company as Holder
deems reasonable, has had the opportunity to ask questions and receive
answers from the Company with respect to its business, assets, prospects and
financial condition and has verified any answers Holder has received from the
Company with independent third parties to the extent Holder deems necessary.
The Holder, by acceptance hereof, acknowledges that the Restricted Securities
are being acquired solely for the Holder's own account and not as a nominee
for any other party, and for investment, and that the Holder will not offer,
sell or otherwise dispose of this Warrant or any Shares to be issued upon
exercise hereof or conversion thereof except under circumstances that will
not result in a violation of the Act or any state securities laws.

         4.2       LEGENDS. The Restricted Securities shall be imprinted with
legends in substantially the following form:

         THIS SECURITY HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF
         1933, AS AMENDED, OR ANY STATE SECURITIES LAW AND MAY NOT BE SOLD,
         PLEDGED OR OTHERWISE TRANSFERRED WITHOUT AN EFFECTIVE REGISTRATION
         THEREOF UNDER SUCH ACT OR LAW OR PURSUANT TO RULE 144 AND ANY STATE
         EXEMPTION FROM REGISTRATION OR AN OPINION OF COUNSEL REASONABLY
         SATISFACTORY TO THE CORPORATION AND ITS COUNSEL THAT SUCH
         REGISTRATION IS NOT REQUIRED.

         THIS SECURITY IS SUBJECT TO CERTAIN RESTRICTIONS UPON TRANSFER,
         INCLUDING BUT NOT LIMITED TO A RIGHT OF FIRST OFFER ON BEHALF OF THE
         COMPANY, AS SET FORTH IN AN AGREEMENT BETWEEN THE COMPANY AND THE
         STOCKHOLDER, A COPY OF WHICH IS ON FILE WITH THE SECRETARY OF THE
         COMPANY.

         4.3       RESTRICTIONS ON TRANSFER.

                   4.3.1     RIGHT OF FIRST REFUSAL. Except as provided
herein, the Holder hereby understands, acknowledges and agrees that the
Warrant may not be sold or otherwise transferred without the Company's prior
written consent. Before the Warrant may be sold or otherwise transferred
(including without limitation a transfer by gift or operation of law) (the
"OFFERED SECURITIES"), the Company and/or its assignee(s) will have a right
of first refusal to purchase the Warrant to be sold or transferred on the
terms and conditions set forth in this Section 4.3.1 (the "RIGHT OF FIRST
REFUSAL").

                                       4

<PAGE>

                             4.3.1.1   NOTICE OF PROPOSED TRANSFER. The
Holder of the Offered Securities will deliver to the Company a written notice
(the "TRANSFER NOTICE") stating: (i) the Holder's bona fide intention to sell
or otherwise transfer the Offered Securities; (ii) the name and address of
each proposed purchaser or other transferee (the "PROPOSED TRANSFEREE");
(iii) the number or portion of such Offered Securities to be transferred to
each Proposed Transferee; (iv) the bona fide cash price or other
consideration for which the Holder proposes to transfer the Offered
Securities (the "OFFERED PRICE"); and (v) that the Holder acknowledges this
Transfer Notice is an offer to sell the Offered Securities to the Company
pursuant to the Company's Right of First Refusal at the Offered Price as
provided for in this Warrant.

                             4.3.1.2   EXERCISE OF RIGHT OF FIRST REFUSAL. At
any time within thirty (30) days after the date of the Transfer Notice, the
Company may, by giving written notice to the Holder, elect to purchase all
(or, with the consent of the Holder, less than all) the Offered Securities
proposed to be transferred to any one or more of the Proposed Transferees
named in the Transfer Notice, at the purchase price determined in accordance
with Subsection 4.3.1.3 below.

                             4.3.1.3   PURCHASE PRICE. The purchase price for
the Offered Securities purchased under this Section will be the Offered
Price, provided that if the Offered Price consists of no legal consideration
(as, for example, in the case of a transfer by gift), the purchase price will
be the fair market value of the Offered Securities as determined in
accordance with Section 1.6 hereof. If the Offered Price includes
consideration other than cash, then the value of the non-cash consideration,
as determined in good faith by the Company's Board of Directors, will
conclusively be deemed to be the cash equivalent value of such non-cash
consideration.

                             4.3.1.4   PAYMENT. Payment of the purchase price
for the Offered Securities will be payable, at the option of the Company, as
applicable, by check, by wire transfer or by cancellation of all or a portion
of any outstanding indebtedness owed by the Holder to the Company (or to such
assignee, in the case of a purchase of Offered Securities by such assignee)
or by any combination thereof. The purchase price will be paid without
interest within three (3) business days after the Company's election to
exercise its Right of First Refusal.

                             4.3.1.5   HOLDER'S RIGHT TO TRANSFER. If the
Company has not elected to exercise its Rights of First Refusal as provided
in Section 4.3.1.2 or Holder has not consented to the purchase of less than
all of the Offered Securities proposed in the Transfer Notice to be
transferred to a given Proposed Transferee by the Company as provided in this
Section, then the Holder may sell or otherwise transfer all such Offered
Securities to each Proposed Transferee at the Offered Price or at a higher
price (and if Holder consented to the purchase of less than all the Offered
Securities proposed in the Transfer Notice to be transferred to a given
Proposed Transferee by the Company as provided in this Section, then the
Holder may sell or otherwise transfer any remaining Offered Securities to
each Proposed Transferee at the Offered Price or at a higher price), provided
that (i) such sale or other transfer is consummated within one hundred twenty
(120) days after the date of the Transfer Notice and (ii) any such sale or
other transfer is effected in compliance with all applicable securities laws.
If the Offered Securities described in the Transfer Notice are not
transferred to each Proposed Transferee within such one hundred twenty (120)
day period, then a new Transfer Notice must be given to the Company, pursuant
to which the Company will again be offered the Right of First Refusal before
the Warrant may be sold or otherwise transferred.

                             4.3.1.6   EXEMPT TRANSFERS. Notwithstanding
anything to the contrary in this Section, the following transfers of the
Warrant will be exempt from the Right of First Refusal: (i) any transfer of
the Warrant made pursuant to a statutory merger or statutory consolidation of
the Company with or into another corporation or corporations (except that the
Right of First Refusal will continue to apply thereafter to the Warrant, in
which case the surviving corporation of such merger or consolidation shall
succeed to the rights of the Company under this Section unless the agreement
of merger or consolidation expressly otherwise provides); (ii) any transfer
of the Warrant pursuant to the winding up and dissolution of the Company; or
(iii) any transfer of the Warrant to any wholly owned subsidiary of Holder.

                             4.3.1.7   TERMINATION OF RIGHT OF FIRST REFUSAL.
The Right of First Refusal will terminate as to the Warrant on the first to
occur of the following: (i) the Expiration Date of this Warrant, or (ii) the
effective date of the registration of the Shares by the Company under the Act
and applicable state securities law, or (iii) the date of expiration of any
statutory holding period applicable to the Shares as required by Rule 144 and
any applicable state exemption from registration.

                                       5

<PAGE>

                             4.3.1.8   ENCUMBRANCES ON THE WARRANT. Holder
may grant a lien or security interest in, or pledge, hypothecate or encumber
the Warrant only if each party to whom such lien or security interest is
granted, or to whom such pledge, hypothecation or other encumbrance is made,
agrees in a writing satisfactory to the Company that: (i) such lien, security
interest, pledge, hypothecation or encumbrance will not apply to the Warrant
after they are acquired by the Company and/or its assignees under this
Section; and (ii) the provisions of this Section will continue to apply to
the Warrant in the hands of such party and any transferee of such party.
Purchaser may not grant a lien or security interest in, or pledge,
hypothecate or encumber any part of this Warrant.

                   4.3.2     SECURITIES LAWS. This Warrant and the Shares
issuable upon exercise of this Warrant may not be transferred or assigned in
whole or in part without compliance with applicable federal and state
securities laws by the transferor and the transferee (including, without
limitation, the delivery of investment representation letters and legal
opinions reasonably satisfactory to the Company, as reasonably requested by
the Company). If, subject to the provisions of this Section 4.3, the Holder
is allowed to transfer this Warrant or the Shares issuable upon exercise of
this Warrant (or the securities issuable, directly or indirectly, upon
conversion of the Shares, if any), the Company shall not require Holder to
provide an opinion of counsel if there is no material question as to the
availability of current information as referenced in Rule 144(c), Holder
represents that it has complied with Rule 144(d) and (e) in reasonable
detail, the selling broker represents that it has complied with Rule 144(f),
and the Company is provided with a copy of Holder's notice of proposed sale
and/or transfer.

         4.4       REGISTRATION.

                   4.4.1      REGISTRATION STATEMENT ON FORM S-3. For use in
the sale of up to 25 percent (25%) of the Shares (the "UNRESTRICTED SHARES"),
within 30 days of the Issue Date, the Company will prepare and file with the
Securities and Exchange Commission ("SEC") a registration statement on Form
S-3 (or such other form that the Company may be eligible to use) relating to
the sale of the Unrestricted Shares by Holder from time to time (the
"REGISTRATION STATEMENT"), and use its reasonable best efforts, subject to
receipt of necessary information from Holder, to cause such Registration
Statement to be declared effective by the SEC as soon as is practicable after
the SEC has completed its review process. The Company agrees to use its
reasonable best efforts to keep such Registration Statement effective until
twelve 12 months after the issue date. The Company shall file all reports
required to be filed by the Company with the SEC in a timely manner and take
all other necessary action so as to maintain such eligibility for the use of
Form S-3 (or its successor or equivalent). Notwithstanding the foregoing,
following the effectiveness of the Registration Statement, the Company may,
at any time, suspend the effectiveness of the Registration Statement (a
"SUSPENSION PERIOD"), by giving written notice to Holder, if the Company
shall have determined that the Company may be required to disclose, update,
correct or provide any material corporate development or information. Holder
agrees that, upon receipt of any notice from the Company of a Suspension
Period, Holder will not sell any Unrestricted Shares pursuant to the
Registration Statement until (i) Holder is advised in writing by the Company
that the use of the applicable prospectus may be resumed, (ii) Holder has
received copies of any additional or supplemental or amended prospectus, if
applicable, and (iii) Holder has received copies of any additional or
supplemental filings which are incorporated or deemed to be incorporated by
reference in such prospectus. The Company will use its reasonable best
efforts to ensure that the use of the Registration Statement may be resumed
as soon as reasonably practicable.

                             4.4.1.1   PUT RIGHT. The first time the Holder
wishes to sell any or all of the Unrestricted Shares pursuant to the
Registration Statement, it shall notify the Company in writing (the "SALE
NOTICE"). The Sale Notice may not be given by the Holder any sooner than 90
days after the Issue Date. If upon receipt of the Sale Notice, the
Registration Statement for the Unrestricted Shares has not been declared
effective for any reason other than for the Holder's failure to provide
necessary information for such Registration Statement, then the Company shall
immediately notify the Holder that such Registration Statement has not been
declared effective (the "COMPANY REGISTRATION NOTICE") and the Holder will
have the right to require the Company to purchase all such Unrestricted
Shares subject to the terms and conditions hereof (the "PUT RIGHT"). Upon
receipt of the Company Registration Notice, the Holder must notify the
Company within three (3) business days as to whether it wishes to exercise
the Put Right (the "PUT EXERCISE NOTICE"). Upon receipt of the Put Exercise
Notice, the Company shall purchase and the Holder shall sell to the Company,
free and clear of any encumbrances, all such Unrestricted Shares by the
Company's paying for each and every share of the Unrestricted Shares subject
to the Put Right an amount equal to the closing price of a share of the
Company's Common Stock as quoted on Nasdaq or any other exchange on which the
Common Stock of the Company is listed as of the date of the receipt of the
Sale Notice by the Company. The closing of the Put Right exercise shall occur
within three (3) business days of Company's receipt of the Put Exercise
Notice. The Put Right shall expire on the date the Registration Statement
first becomes effective.

                                       6

<PAGE>

                   4.4.2     DELIVERY OF PROSPECTUS. The Company shall
furnish to Holder promptly after the Registration Statement is prepared and
publicly distributed, filed with the SEC, or received by the Company, one
copy of the Registration Statement and any amendment thereto, each
preliminary prospectus and prospectus and each amendment or supplement
thereto. The Company shall furnish to Holder such number of copies of
prospectuses and preliminary prospectuses in conformity with the requirements
of the Securities Act, in order to facilitate the public sale or other
disposition of all or any of the Unrestricted Shares by Holder; provided,
however, that the obligation of the Company to deliver copies of prospectuses
or preliminary prospectuses to the Holder shall be subject to the receipt by
the Company of reasonable assurances from Holder that Holder will comply with
the applicable provisions of the Securities Act and of such other securities
or blue sky laws as may be applicable in connection with any use of such
prospectuses or preliminary prospectuses. The Company shall bear all expenses
incurred by the Company in connection with the registration of the
Unrestricted Shares pursuant to the Registration Statement (but excluding
underwriters' and brokers' discounts and commissions), and the reasonable
fees and disbursements (not to exceed $10,000 in the aggregate) of a single
special counsel for Holder.

                   4.4.3     INFORMATION. It shall be a condition precedent
to the obligations of the Company to take any action pursuant to Section
4.4.1 that Holder shall provide such information regarding itself, the
Unrestricted Shares held by them, the intended method of disposition of the
Unrestricted Shares and such other information as the Company may reasonably
request to timely effect the registration of the Unrestricted Shares.

                   4.4.4     INDEMNIFICATION. For the purpose of this Section
4.4.4, the term "Registration Statement" shall include any final prospectus,
exhibit, supplement or amendment included in or relating to the Registration
Statement referred to in Section 4.4.1.

                             (a) The Company agrees to indemnify and hold
harmless Holder, each of its directors and officers, any underwriters (as
defined in the Securities Act) for Holder and each person, if any, who
controls Holder within the meaning of the Securities Act, against any losses,
claims, damages, liabilities or expenses to which Holder or such officer or
director, underwriter or controlling person may become subject, under the
Securities Act, the Securities Exchange Act of 1934, as amended (the
"EXCHANGE ACT"), or any other federal or state statutory law or regulation,
or at common law or otherwise (including in settlement of any litigation, if
such settlement is effected with the written consent of the Company), insofar
as such losses, claims, damages, liabilities or expenses (or actions in
respect thereof as contemplated below) arise out of or are based upon (i) any
untrue statement or alleged untrue statement of any material fact contained
in the Registration Statement, including the prospectus, financial statements
and schedules, and all other documents filed as a part thereof or
incorporated by reference therein, as amended at the time of effectiveness of
the Registration Statement, including any information deemed to be a part
thereof as of the time of effectiveness pursuant to paragraph (b) of Rule
430A,or pursuant to Rule 434, of the Rules and Regulations, or the
prospectus, in the form first filed with the SEC pursuant to Rule 424(b) of
the Regulations, or filed as part of the Registration Statement at the time
of effectiveness if no Rule 424(b) filing is required (the "PROSPECTUS"), or
any amendment or supplement thereto, (ii) the omission or alleged omission to
state in any of them a material fact required to be stated therein or
necessary to make the statements in any of them not misleading, or (iii) any
violation or alleged violation by the Company of the Securities Act, the
Exchange Act or any federal or state securities law in connection with the
offering covered by such registration statement (the matters in the foregoing
clauses (i) through (iii) being, collectively, "VIOLATIONS"), and will
reimburse Holder and each such officer or director, underwriter or
controlling person for any legal and other expenses as such expenses are
reasonably incurred by Holder or such controlling person in connection with
investigating, defending, settling, compromising or paying any such loss,
claim, damage, liability, expense or action; provided, however, the indemnity
agreement contained in this Section 4.4.4(a) shall not apply to amounts paid
in settlement of any such loss, claim, damage, liability, expense or action
if such settlement is effected without the consent of the Company (which
consent shall not be unreasonably withheld or delayed) and provided, further,
that the Company will not be liable in any such case to the extent that any
such loss, claim, damage, liability or expense arises out of or is based upon
an untrue statement or alleged untrue statement or omission or alleged
omission made in the Registration Statement, the Prospectus or any amendment
or supplement thereto in reliance upon and in conformity with (i) written
information furnished to the Company by or on behalf of Holder expressly for
use therein or (ii) the failure of Holder to comply with the covenants and
agreements contained in this Warrant respecting the sale of the Unrestricted
Shares, the inaccuracy of any representations made by Holder herein or any
statement or omission in any Prospectus that is corrected in any subsequent
Prospectus that was delivered to Holder prior to the pertinent sale or sales
by Holder.

                             (b) Holder will indemnify and hold harmless the
Company, each of its directors, each of its officers who signed the
Registration Statement and each person, if any, who controls the Company
within the meaning of the Securities Act, against any losses, claims,
damages, liabilities or expenses to which the Company,

                                       7

<PAGE>

each of its directors, each of its officers who signed the Registration
Statement or controlling person may become subject, under the Securities Act,
the Exchange Act, or any other federal or state statutory law or regulation,
or at common law or otherwise (including in settlement of any litigation, if
such settlement is effected with the written consent of Holder) insofar as
such losses, claims, damages, liabilities or expenses (or actions in respect
thereof as contemplated below) arise out of or are based upon any Violation,
in each case to the extent, but only to the extent, that such Violation
occurs in reliance upon and in conformity with written information furnished
to the Company by or on behalf of any Holder expressly for use therein, and
will reimburse the Company, each of its directors, each of its officers who
signed the Registration Statement or controlling person for any legal and
other expense reasonably incurred by the Company, each of its directors, each
of its officers who signed the Registration Statement or controlling person
in connection with investigating, defending, settling, compromising or paying
any such loss, claim, damage, liability, expense or action; provided,
however, the indemnity agreement contained in this Section 4.4.4(b) shall not
apply to amounts paid in settlement of any such loss, claim, damage,
liability, expense or action if such settlement is effected without the
consent of the Holder (which consent shall not be unreasonably withheld or
delayed). Notwithstanding the foregoing, in no event shall any indemnity
under this Section 4.4.4(b) exceed the proceeds from the offering of Shares
made under the Registration Statement.

                             (c) Promptly after receipt by an indemnified
party under this Section 4.4.4 of notice of the commencement of any action,
such indemnified party will, if a claim in respect thereof is to be made
against an indemnifying party under this Section 4.4.4, notify the
indemnifying party in writing of the commencement thereof; but the omission
so to notify the indemnifying party will not relieve it from any liability
which it may have to any indemnified party for contribution or otherwise than
under the indemnity agreement contained in this Section 4.4.4 or to the
extent it is not prejudiced as a proximate result of such failure. In case
any such action is brought against any indemnified party and such indemnified
party seeks or intends to seek indemnity from an indemnifying party, the
indemnifying party will be entitled to participate in, and, to the extent
that it may wish, jointly with all other indemnifying parties similarly
notified, to assume the defense thereof with counsel reasonably satisfactory
to such indemnified party; provided, however, if the defendants in any such
action include both the indemnified party and the indemnifying party and the
indemnified party shall have reasonably concluded that there may be a
conflict between the positions of the indemnifying party and the indemnified
party in conducting the defense of any such action or that there may be legal
defenses available to it and/or other indemnified parties which are different
from or additional to those available to the indemnifying party, the
indemnified party or parties shall have the right to select separate counsel
reasonably acceptable to the indemnifying party to assume such legal defenses
and to otherwise participate in the defense of such action on behalf of such
indemnified party or parties. Upon receipt of notice from the indemnifying
party to such indemnified party of its election so to assume the defense of
such action and approval by the indemnified party of counsel, the
indemnifying party will not be liable to such indemnified party under this
Section 4.4.4 for any legal or other expenses subsequently incurred by such
indemnified party in connection with the defense thereof unless (i) the
indemnified party shall have employed such counsel in connection with the
assumption of legal defenses in accordance with the proviso to the preceding
sentence (it being understood, however, that the indemnifying party shall not
be liable for the expenses of more than one separate counsel, approved by
such indemnifying party in the case of paragraph (a), representing the
indemnified parties who are parties to such action) or (ii) the indemnified
party shall not have employed counsel reasonably satisfactory to the
indemnified party to represent the indemnified party within a reasonable time
after notice of commencement of action, in each of which cases the fees and
expenses of counsel shall be at the expense of the indemnifying party.

                             (d) The foregoing indemnity agreements of the
Company and Holder are subject to the condition that, insofar as they relate
to the bases for any losses, claims, damages, liabilities or expenses
contemplated in Section 4.4.4(a) arising out of the preparation and filing of
the preliminary prospectus but eliminated or remedied in the amended
prospectus on file with the SEC at the time the registration statement in
question becomes effective or the amended prospectus filed with the SEC
pursuant to SEC Rule 424(b) (the "FINAL PROSPECTUS"), such indemnity
agreement shall not inure to the benefit of any person if a copy of the Final
Prospectus was furnished to the indemnified party and was not furnished to
the person asserting the loss, liability, claim or damage at or prior to the
time such action is required by the Securities Act.

         4.5       TRANSFER PROCEDURE. If, subject to the provisions of
Section 4.3, Holder is allowed to transfer all or part of this Warrant,
Holder shall give the Company a written notice of the portion of the Warrant
being transferred, such notice setting forth the name, address and taxpayer
identification number of the transferee, and, together with such notice,
Holder shall surrender this Warrant to the Company for reissuance to the
transferee (and to the new Warrant Holder for any remaining Shares, if
applicable). As a condition to sale, transfer or assignment (other than
pursuant to the Registration Statement under Section 4.4) of this Warrant and
the Shares issuable upon exercise of this Warrant, the Holder shall confirm,
acknowledge and agree to the representations, warranties and agreements

                                       8

<PAGE>

forth in Section 4 hereof.

5.       GENERAL PROVISIONS.

         5.1       NOTICES. Any and all notices and Transfer Notices required
or permitted to be given to a party pursuant to the provisions of this
Warrant will be in writing and will be effective and deemed to provide such
party sufficient notice under this Warrant on the earliest of the following:
(i) at the time of personal delivery, if delivery is in person; (ii) at the
time of transmission by facsimile, addressed to the other party at its
facsimile number specified herein (or hereafter modified by subsequent notice
to the parties hereto), with confirmation of receipt made by both telephone
and printed confirmation sheet verifying successful transmission of the
facsimile; (iii) one (1) business day after deposit with an express overnight
courier for United States deliveries, or two (2) business days after such
deposit for deliveries outside of the United States, with proof of delivery
from the courier requested; or (iv) three (3) business days after deposit in
the United States mail by certified mail (return receipt requested) for
United States deliveries.

                   All notices for delivery outside the United States will be
sent by facsimile or by express courier. All notices not delivered personally
or by facsimile will be sent with postage and/or other charges prepaid and
properly addressed to the party to be notified at the address or facsimile
number set forth below the signature lines to this Warrant, or at such other
address or facsimile number as such other party may designate by one of the
indicated means of notice herein to the other parties hereto. Notices to the
Company will be marked "Attention: President". Notices by facsimile shall be
machine verified as received.

         5.2       GOVERNING LAW. This Warrant will be governed by and
construed in accordance with the laws of the State of California, without
giving effect to that body of laws pertaining to conflict of laws.

         5.3       FURTHER ASSURANCES. The parties agree to execute such
further documents and instruments and to take such further actions as may be
reasonably necessary to carry out the purposes and intent of this Warrant.

         5.4       TITLES AND HEADINGS. The titles, captions and headings of
this Warrant are included for ease of reference only and will be disregarded
in interpreting or construing this Warrant. Unless otherwise specifically
stated, all references herein to "sections" and "exhibits" will mean
"sections" and "exhibits" to this Warrant.

         5.5       COUNTERPARTS. This Warrant may be executed in any number
of counterparts, each of which when so executed and delivered will be deemed
an original, and all of which together shall constitute one and the same
agreement.

         5.6       SEVERABILITY. If any provision of this Warrant is
determined by any court or arbitrator of competent jurisdiction to be
invalid, illegal or unenforceable in any respect, such provision will be
enforced to the maximum extent possible given the intent of the parties
hereto. If such clause or provision cannot be so enforced, such provision
shall be stricken from this Warrant and the remainder of this Warrant shall
be enforced as if such invalid, illegal or unenforceable clause or provision
had (to the extent not enforceable) never been contained in this Warrant.
Notwithstanding the forgoing, if the value of this Warrant based upon the
substantial benefit of the bargain for any party is materially impaired,
which determination as made by the presiding court or arbitrator of competent
jurisdiction shall be binding, then both parties agree to substitute such
provision(s) through good faith negotiations.

         5.7       FACSIMILE SIGNATURES. This Warrant may be executed and
delivered by facsimile and upon such delivery the facsimile signature will be
deemed to have the same effect as if the original signature had been
delivered to the other party. The original signature copy shall be delivered
to the other party by express overnight delivery. The failure to deliver the
original signature copy and/or the nonreceipt of the original signature copy
shall have no effect upon the binding and enforceable nature of this Warrant.

         5.8       AMENDMENT AND WAIVERS. This Warrant may be amended only by
a written agreement executed by each of the parties hereto. No amendment of
or waiver of, or modification of any obligation under this Warrant will be
enforceable unless set forth in a writing signed by the party against which
enforcement is sought. Any amendment effected in accordance with this Section
5.8 will be binding upon all parties hereto and each of their respective
successors and assigns. No delay or failure to require performance of any
provision of this Warrant shall constitute a waiver of that provision as to
that or any other instance. No waiver granted under this Warrant as to any

                                       9

<PAGE>

one provision herein shall constitute a subsequent waiver of such provision
or of any other provision herein, nor shall it constitute the waiver of any
performance other than the actual performance specifically waived.

         5.9       ENTIRE AGREEMENT. This Warrant and the documents referred
to herein, including but not limited to the Development and Marketing
Agreement between Company and Holder dated of even date herewith, constitute
the entire agreement and understanding of the parties with respect to the
subject matter of this Warrant, and supersede all prior understandings and
agreements, whether oral or written, between or among the parties hereto with
respect to the specific subject matter hereof.

WARRANT HOLDER:                             COMPANY:


/s/ William J. Brown                        /s/ Robert L. Schultz, Jr.
--------------------------------            -------------------------------
AGILENT TECHNOLOGIES, INC.                  ADAPTEC, INC.

Name: William J. Brown                      Name: Robert L. Schultz, Jr.
     ---------------------------                 --------------------------

Title: Senior Vice President and            Title: Chief Operating Officer
       General Manager                            -------------------------
      --------------------------



                                       10

<PAGE>

                                    EXHIBIT A

                               NOTICE OF EXERCISE

                  (TO BE SIGNED ONLY UPON EXERCISE OF WARRANT)

1.  PLEASE MARK ONE OF THE FOLLOWING:

[ ] 1.1 CASH EXERCISE ELECTION. The undersigned hereby elects to purchase
___________ shares of the Common Stock of ADAPTEC, INC., a Delaware
corporation, pursuant to the terms of the attached Warrant to Purchase Stock
with an Issue Date of January 17, 2000 (the "WARRANT"), and the Undersigned
tenders herewith payment of the total purchase price of such shares in full,
pursuant to a check or wire transfer, in the amount of $__________.

OR


[ ] 1.2 NET EXERCISE ELECTION. The undersigned Holder elects to convert all
or part of the Warrant into shares of stock by net exercise election pursuant
to Section 1.6 of the Warrant. This conversion is exercised with respect to
__________ shares of Common Stock of ADAPTEC, INC. covered by the Warrant.

         2. Please issue a certificate or certificates representing said
shares in the name of the undersigned. The undersigned represents that it is
acquiring the shares solely for its own account and not as a nominee for any
other party and not with a view toward the resale or distribution thereof
except in compliance with applicable securities laws and hereby confirms and
agrees to the representations, warranties and agreements that are set forth
in Section 4 of the attached Warrant.


                                          ------------------------------------
                                          (Name)


                                          ------------------------------------

                                          ------------------------------------

                                          ------------------------------------
                                          Address


                                          ------------------------------------
                                          (Signature of Holder)


                                       1

<PAGE>

                                     AMENDMENT

                                        OF

                             WARRANT TO PURCHASE STOCK

                                        OF

                                   ADAPTEC, INC.



     This Amendment is made effective as of February 14, 2000 between
Adaptec, Inc. (the "COMPANY") and Agilent Technologies, Inc., the "HOLDER"
(as defined in the Warrant) of that certain Warrant to Purchase Stock, Issue
Date of January 17, 2000, providing for the purchase of 696,000 shares of the
Common Stock of the Company at an Initial Exercise Price of $62.25 per share
(the "WARRANT").  Capitalized terms used herein and not otherwise defined
shall have the meanings ascribed to them in the Warrant.


                                      RECITAL

     WHEREAS, the Company and the undersigned Holder desire to amend the
Warrant to adequately reflect their current understanding of their rights and
obligations under the Warrant.


                                    AGREEMENT

NOW THEREFORE, pursuant to Section 5.8 of the Warrant, the Company and the
Holder hereby agree as follows:

         1.     To amend the Warrant so that the portion of Section 4.4.1 of
the Warrant which reads "within 30 days of the Issue Date" is deleted and is
replaced by "as soon as reasonably possible but in no event later than 51
days of the Issue Date"; and


         2.     That all other provisions of the Warrant shall remain in full
force and effect.


         This Amendment may be executed in any number of counterparts, each
of which shall be deemed an original and enforceable against the parties
actually executing such counterpart, and all of which together shall
constitute one instrument.

<PAGE>

         This Amendment is executed and is effective as of the date first set
forth above.



COMPANY:

ADAPTEC, INC.

By: /s/ Andrew J. Brown
   ----------------------------------

Name: Andrew J. Brown
     --------------------------------

Title: Vice President, Finance and Chief Financial Officer
     -----------------------------------------------------


HOLDER:

AGILENT TECHNOLOGIES, INC.

By: /s/ William P. Sullivan
   ----------------------------------

Name: William P. Sullivan
     --------------------------------

Title: Senior Vice President and General Manager
     -----------------------------------------------------



1002706





[SIGNATURE PAGE TO THE AMENDMENT OF WARRANT TO PURCHASE STOCK OF ADAPTEC, INC.]