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                                                        Exhibit 3.47

                                                     ENDORSED - FILED
                                         IN THE OFFICE OF THE SECRETARY OF STATE
                                                OF THE STATE OF CALIFORNIA

                                                        DEC 13 2002

                                               BILL JONES, SECRETARY OF STATE

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

         We, Robert W. Riland III 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 said Corporation, said Board of Directors on
July 31, 2002 adopted the following resolution adding 10,067 shares of Preferred
Stock designated as Series W Preferred Stock (the "Additional Series W
Preferred") to the 30,201 shares of Series W Preferred Stock previously
authorized by the Board on December 31, 1999, none of which Additional Series W
Preferred shares have been issued as of the date hereof:

                  "RESOLVED: That the Board approves of an amendment and
         restatement of the Original Series W Certificate to increase the number
         of authorized shares of Series W Preferred Stock, initially consisting
         of 30,201 shares, by 10,067 shares, such that the total authorized
         number of shares shall be 40,268. The designations, powers, preferences
         and relative and other special rights and the qualifications,
         limitations and restrictions of the additional shares of Series W
         Preferred Stock shall be as set forth in the Original Series W
         Certificate."

         The Certificate of Determination of Preferences of Series W Preferred
Stock is hereby amended and restated 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 40,268.

                  Section 2. Dividends and Distributions.

                           (A)      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 Stock, Series Q
         Preferred Stock, Series R Preferred Stock, Series S Preferred Stock,
         Series T Preferred Stock, Series U Preferred Stock, 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

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         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 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 Stock, Series Q Preferred
         Stock, Series R Preferred Stock, Series S Preferred Stock, Series T
         Preferred Stock, Series U Preferred Stock, Series V Preferred Stock,
         dividends shall simultaneously be declared and paid on the outstanding
         shares of Series W Preferred Stock, pari passu with the 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 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, based upon the number of shares of Common Stock into
         which 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
         Stock, Series Q Preferred Stock, Series R Preferred Stock, Series S
         Preferred Stock, Series T Preferred Stock, Series U Preferred Stock,
         Series V Preferred Stock, and Series W Preferred Stock are then
         convertible. In the event the Corporation shall at any time after the
         date of the filing of this Amended 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 sentence 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. Except as provided by law, the Common Stock and Series W
         Preferred Stock (and any series of Preferred Stock which may be
         subsequently authorized which is convertible into shares of Common
         Stock and which has 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 a single class on all matters to
         come before the shareholders for approval. 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

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         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 series of Preferred Stock which may
         be subsequently authorized which is convertible into shares of Common
         Stock and which has 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

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         thereof, securities of the Corporation or any of its 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 $.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 plus any declared but unpaid dividends ("Series O Liquidation
         Preference"), the liquidation preference of the Series P Preferred
         Stock in the amount of $8.20 per share plus any declared but unpaid
         dividends ("Series P Liquidation Preference"), the liquidation
         preference of the Series Q Preferred Stock in the amount of $6.20 per
         share plus any declared but unpaid dividends ("Series Q Liquidation
         Preference"), the liquidation preference of the Series R Preferred
         Stock in the amount of $5.80 share plus any declared but unpaid
         dividends ("Series R Liquidation Preference"), the liquidation
         preference of the Series S Preferred Stock in the amount of $3.20 per
         share plus any declared but unpaid dividends ("Series S Liquidation
         Preference"), the liquidation preference of the Series T Preferred
         Stock in the amount of $20.20 per share plus any declared but unpaid
         dividends ("Series T Liquidation Preference"), the liquidation
         preference of the Series U Preferred Stock in the amount of $15.40 per
         share plus any

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         declared but unpaid dividends ("Series U Liquidation Preference"), the
         liquidation preference of the Series V Preferred Stock in the amount of
         $10.60 per share plus any declared but unpaid dividends ("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, and 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 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, receive dividends, participate in distributions and to have the
         benefit of all other rights of holders of Series W Preferred Stock.

                  (remainder of page intentionally left blank)

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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 12, 2002.

                                          /s/ Robert W. Riland III
                                          -------------------------------------
                                          Robert W. Riland III
                                          President and Chief Executive Officer

                                          /s/ Henry Madrid
                                          -------------------------------------
                                          Henry Madrid
                                          Chief Financial Officer

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