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                                  EXHIBIT 3.24


                   CERTIFICATE OF DETERMINATION OF PREFERENCES
                                       OF
                            SERIES W PREFERRED STOCK
                                       OF
                                   DISC, INC.

     We, J. Richard Ellis and Henry Madrid, hereby certify that we are the
President and the Chief Financial Officer, respectively, of DISC, INC., a
corporation organized and existing under the General Corporation Law of the
State of California, and further, DO HEREBY CERTIFY:

     That pursuant to the authority conferred upon the Board of Directors by the
Articles of Incorporation of the said Corporation, the said Board of Directors
on December 31, 1999 adopted the following resolution creating a series of
30,201 shares of Preferred Stock designated as Series W Preferred Stock, none of
which shares have been issued:

          "RESOLVED, that pursuant to the authority vested in the Board of
     Directors of the corporation by the Articles of Incorporation, the Board of
     Directors does hereby provide for the issuance of a series of Preferred
     Stock, no par value, of the Corporation, to be designated "Series W
     Preferred Stock," initially consisting of 30,201 shares and to the extent
     that the designations, powers, preferences and relative and other special
     rights and the qualifications, limitations and restrictions of the Series W
     Preferred Stock are not stated and expressed in the Articles of
     Incorporation, does hereby fix and herein state and express such
     designations, powers, preferences and relative and other special rights and
     the qualifications, limitations and restrictions thereof, as follows (all
     terms used herein which are defined in the Articles of Incorporation shall
     be deemed to have the meanings provided therein):

          Section 1. Designation and Amount. The shares of such series shall be
     designated as "Series W Preferred Stock," no par value, and the number of
     shares constituting such series shall be 30,201.

          Section 2. Dividends and Distributions.

               Subject to the prior and superior right of the holders of any
     shares of Series C Preferred Stock ranking prior and superior to the shares
     of Series W Preferred Stock with respect to dividends, and pari passu with
     the rights of the holders of shares of Series D Preferred Stock, Series E
     Preferred Stock, Series F Preferred Stock, Series G Preferred Stock, Series
     H Preferred Stock, Series I Preferred Stock, Series J Preferred Stock,
     Series K Preferred Stock, Series L Preferred Stock, Series M Preferred
     Stock, Series N Preferred Stock, Series O Preferred Stock, Series P
     Preferred


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     Stock, Series Q Preferred Stock, Series R Preferred Stock, Series S
     Preferred Stock, Series T Preferred Stock, Series U Preferred Stock and
     Series V Preferred Stock with respect to dividends, subject to the rights
     of any series of Preferred Stock which may hereafter come into existence,
     the holders of shares of Series W Preferred Stock shall be entitled to
     receive when, as and if declared by the Board of Directors out of funds
     legally available for the purpose, dividends in the same amount per share
     as declared on the Common Stock, treating such number of shares of Series W
     Preferred Stock for this purpose as equal to the number of shares of Common
     Stock into which it is then convertible. In the event any dividends are
     declared or paid on the outstanding shares of any series of Preferred Stock
     with dividend rights ranking pari passu with the Series W Preferred Stock,
     dividends shall simultaneously be declared and paid on the outstanding
     shares of Series W Preferred Stock, pari passu with the shares of such
     other series of Preferred Stock with dividend rights ranking pari passu
     with the Series W Preferred Stock, based upon the number of shares of
     Common Stock into which shares of Series W Preferred Stock and such other
     series of Preferred Stock with dividend rights ranking pari passu with the
     Series W Preferred Stock are then convertible. In the event the Corporation
     shall at any time after the date of the filing of this Certificate of
     Determination of Preferences (the "Rights Declaration Date") (i) declare
     any dividend on Common Stock payable in shares of Common Stock, (ii)
     subdivide the outstanding Common Stock, or (iii) combine the outstanding
     Common Stock into a smaller number of shares, then in each such case, the
     amount of Common Stock or other consideration to which holders of shares of
     Series W Preferred Stock were entitled immediately prior to such event
     under the preceding sentences of this Section 2(A) shall be adjusted as set
     forth in Section 4(C) hereof.

                  (B)  The Corporation shall declare a dividend or distribution
     on the Series W Preferred Stock as provided in paragraph (A) above prior to
     declaring a dividend payable on shares of Common Stock.

          Section 3. Voting Rights. The holders of shares of Series W Preferred
     Stock shall have the following voting rights:

                  (A)  Each holder of Series W Preferred Stock is entitled to a
     number of votes equal to the number of shares of Common Stock into which
     the holder's Series W Preferred Stock is then convertible. In the event the
     Corporation shall at any time after the Rights Declaration Date (i) declare
     any dividend on Common Stock payable in shares of Common Stock, (ii)
     subdivide the outstanding Common Stock, or (iii) combine the outstanding
     Common Stock into a smaller number of shares, then in each such case the
     number of votes per share to which holders of shares of Series W Preferred
     Stock were entitled immediately prior to such event shall be adjusted as
     set forth in Section 4(C) hereof.

                  (B)  Except as otherwise provided herein or by law, the
     holders of shares of Series W Preferred Stock and the holders of shares of
     Common Stock (and any authorized series of Preferred Stock convertible into
     shares of Common Stock and with voting rights equal to the number of shares
     of Common Stock into which such series of Preferred Stock is then
     convertible) shall vote together as one class on all matters submitted to a
     vote of shareholders of the Corporation.

                  (C)  Except as required by law or under Section 8 hereof,
     holders of Series W Preferred Stock shall have no special voting rights and
     their consent shall not be required (except to the extent they are entitled
     to vote with holders of Common Stock as set forth herein) for taking any
     corporate action.

          Section 4. Conversion Rights.

                  (A)  Each holder of Series W Preferred Stock may, at any time,
     in such holder's sole discretion, convert all or any part of such holder's
     shares of Series W Preferred Stock into fully paid and nonassessable shares
     of Common Stock at the rate of ten (10) shares of Common Stock for each
     share of Series W Preferred Stock surrendered for conversion.

                  (B)  Such conversion may be effected by surrender of such
     holder's certificate or certificates for the shares of Series W Preferred
     Stock to be converted, duly endorsed, at the principal office of the
     Corporation, with a written notice stating (i) that such holder elects to
     convert all or a specified number of shares of Series W Preferred Stock
     into shares of Common Stock, and (ii) the name in which such holder desires
     a certificate for the shares of Common Stock to be issued. Promptly
     thereafter, the Company shall issue and deliver to such holder a
     certificate for the number of shares of Common Stock to which such holder
     shall be entitled. Such conversion shall be deemed to have been made at the
     close of business on the date of such surrender, and such holder shall be
     treated for all purposes as the record holder of such shares of Common
     Stock on that date.

                  (C)  In the event the Corporation shall at any time after the
     Rights Declaration Date (i) declare any dividend on Common Stock payable in
     shares of Common Stock, (ii) subdivide the outstanding Common Stock, or
     (iii) combine the outstanding Common Stock into a smaller number of shares,
     then, in each case, the number of shares of Common Stock issuable upon the
     conversion of each share of Series W Preferred Stock shall be adjusted by
     multiplying such amount by a fraction, the numerator of which is the number
     of shares of Common Stock outstanding immediately after such event and the
     denominator of which is the number of shares of Common Stock that are
     outstanding immediately prior to such event.

                  (D)  In the event the Corporation shall at any time or from
     time to time after the Rights Declaration Date make or issue, or fix a
     record date for the determination of holders of Common Stock entitled to
     receive, a dividend or other distribution payable in securities of the
     Corporation or any of its subsidiaries, or of any other corporation or
     third party, other than in shares of Common Stock, then, in each such
     event, provisions shall be made so that the holders of Series W Preferred
     Stock shall receive, upon the conversion thereof, securities of the
     Corporation or any of its


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     subsidiaries or of any other corporation or third party which they would
     have received had their stock been converted into Common Stock on the date
     of such event.

          Section 5. Reacquired Shares. Any shares of Series W Preferred Stock
     purchased or otherwise acquired by the Corporation in any manner whatsoever
     shall be retired and canceled promptly after the acquisition thereof. All
     such shares shall upon their cancellation become authorized but unissued
     shares of Preferred Stock and may be reissued as part of a new series of
     Preferred Stock to be created by resolution or resolutions of the Board of
     Directors, subject to the conditions and restrictions on issuance set forth
     herein.

          Section 6. Liquidation, Dissolution or Winding Up.

                  (A)  Upon any liquidation (voluntary or otherwise),
     dissolution or winding up of the Corporation, following the first priority
     liquidation preference of the Series C Preferred Stock in the amount of
     $5.00 per share plus any declared but unpaid dividends, and pari passu with
     the liquidation preference of the Series D Preferred Stock in the amount of
     $5.00 per share plus any declared but unpaid dividends ("Series D
     Liquidation Preference"), the liquidation preference of the Series E
     Preferred Stock in the amount of $4.00 per share plus any declared but
     unpaid dividends ("Series E Liquidation Preference"), the liquidation
     preference of the Series F Preferred Stock in the amount of $8.00 per share
     plus any declared but unpaid dividends ("Series F Liquidation Preference"),
     the liquidation preference of the Series G Preferred Stock in the amount of
     $20.00 per share plus any declared but unpaid dividends ("Series G
     Liquidation Preference"), the liquidation preference of the Series H
     Preferred Stock in the amount of $38.30 per share plus any declared but
     unpaid dividends ("Series H Liquidation Preference"), the liquidation
     preference of the Series I Preferred Stock in the amount of $4.19 per share
     plus any declared but unpaid dividends ("Series I Liquidation Preference"),
     the liquidation preference of the Series J Preferred Stock in the amount of
     $2.98 per share plus any declared but unpaid dividends ("Series J
     Liquidation Preference"), the liquidation preference of the Series K
     Preferred Stock in the amount of $3.19 per share plus any declared but
     unpaid dividends ("Series K Liquidation Preference"), the liquidation
     preference of the Series L Preferred Stock in the amount of $2.76 per share
     plus any declared but unpaid dividends ("Series L Liquidation Preference"),
     the liquidation preference of the Series M Preferred Stock in the amount of
     $2.23 per share plus any declared but unpaid dividends ("Series M
     Liquidation Preference"), the liquidation preference of the Series N
     Preferred Stock in the amount of $0.90 per share plus any declared but
     unpaid dividends ("Series N Liquidation Preference"), the liquidation
     preference of the Series O Preferred Stock in the amount of $1.06 per share
     of Series O Preferred Stock plus any declared but unpaid dividends (the
     "Series O Liquidation Preference"), the liquidation preference of the
     Series P Preferred Stock in the amount of $8.20 per share of Series P
     Preferred Stock plus any declared but unpaid dividends (the "Series P
     Liquidation Preference"), the liquidation preference of the Series Q
     Preferred Stock in the amount of $6.20 per share of Series Q Preferred
     Stock plus any declared but unpaid dividends (the "Series Q Liquidation
     Preference"), the liquidation preference of the Series R Preferred Stock in
     the amount of $5.80 per share of Series R Preferred Stock plus any declared
     but unpaid dividends (the "Series R Liquidation Preference"), the
     liquidation preference of Series S Preferred Stock in the amount of $3.20
     per share of Series S Preferred Stock plus any declared but unpaid
     dividends (the "Series S Liquidation Preference"), the liquidation
     preference of Series T Preferred Stock in the amount of $20.20 per share of
     Series T Preferred Stock plus any declared but unpaid dividends (the
     "Series T Liquidation Preference"), the liquidation preference of Series U
     Preferred Stock in the amount of $15.40 per share of Series U Preferred
     Stock plus any declared but unpaid dividends (the "Series U Liquidation
     Preference") and the liquidation preference of Series V Preferred Stock in
     the amount of $10.60 per share of Series V Preferred Stock plus any
     declared but unpaid dividends (the "Series V Liquidation Preference"), no
     distribution shall be made to the holders of shares of stock ranking junior
     (either as to dividends or upon liquidation, dissolution or winding up) to
     the Series W Preferred Stock unless, prior thereto, the holders of shares
     of Series W Preferred Stock shall have received an amount equal to $14.90
     per share of Series W Preferred Stock plus any declared but unpaid
     dividends ("Series W Liquidation Preference").

                  (B)  In the event, however, that there are not sufficient
     assets available to permit payment in full of the Series D Liquidation
     Preference, the Series E Liquidation Preference, the Series F Liquidation
     Preference, the Series G Liquidation Preference, the Series H Liquidation
     Preference, the Series I Liquidation Preference, the Series J Liquidation
     Preference, the Series K Liquidation Preference, the Series L Liquidation
     Preference, the Series M Liquidation Preference, the Series N Liquidation
     Preference, the Series O Liquidation Preference, the Series P Liquidation
     Preference, the Series Q Liquidation Preference, the Series R Liquidation
     Preference, the Series S Liquidation Preference, the Series T Liquidation
     Preference, the Series U Liquidation Preference, the Series V Liquidation
     Preference, the Series W Liquidation Preference and the liquidation
     preferences of all other series of Preferred Stock, if any, which rank on a
     parity with the Series W Preferred Stock, then such remaining assets shall
     be distributed ratably to the holders of such parity shares in proportion
     to their respective liquidation preferences.

          Section 7. No Redemption. The shares of Series W Preferred Stock shall
     not be redeemable.

          Section 8. Amendment. The Articles of Incorporation of the Corporation
     shall not be further amended in any manner which would (a) alter or change
     the powers, preferences or special rights or privileges of the Series W
     Preferred Stock so as to affect them adversely or (b) grant to any other
     class of shares any rights superior to those of the Series W


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     Preferred Stock without the affirmative vote of the holders of a majority
     or more of the outstanding shares of Series W Preferred Stock, voting
     separately as a class.

          Section 9.  Fractional Shares. Series W Preferred Stock may be issued
     in fractions of a share which shall entitle the holder, in proportion to
     such holder's fractional shares, to exercise voting rights, to receive
     dividends, to participate in distributions and to have the benefit of all
     other rights of holders of Series W Preferred Stock."


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     The undersigned declare under penalty of perjury that the matters set forth
in the foregoing Certificate are true of their own knowledge.

     Executed at Milpitas, California on December 31, 1999.



                                                    /S/  J. Richard Ellis
                                           -------------------------------------
                                           J. Richard Ellis
                                           President and Chief Executive Officer



                                                     /S/  Henry Madrid
                                           -------------------------------------
                                           Henry Madrid
                                           Chief Financial Officer