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                                                                   Exhibit 3.11


                  CERTIFICATE OF DETERMINATION OF PREFERENCES
                                       OF
                            SERIES J 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, 1996 adopted the following resolution creating a
series of 244,966 shares of Preferred Stock designated as Series J 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 J Preferred Stock," initially consisting of 244,966 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 J 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 J Preferred Stock," no par value, and the
        number of shares constituting such series shall be 244,966.

                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 J 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 and Series I
        Preferred Stock with respect to dividends, the holders of shares of
        Series J 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 J 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 and Series I Preferred Stock, dividends shall
        simultaneously be declared
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and paid on the outstanding shares of Series J 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 and Series
I 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 and Series J 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 J
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 J 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 J Preferred
Stock shall have the following voting rights:

                 (A)      Each holder of Series J Preferred Stock is entitled
to a number of votes equal to the number of shares of Common Stock into which
the holder's Series J Preferred Stock is then convertible.  Except as provided
by law, the Common Stock and Series J 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 per share to which holders
of shares of Series J 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 J 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 J 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.


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        Section 4.  Conversion Rights.

                 (A)     Each holder of Series J Preferred Stock may, at any
time, in such holder's sole discretion, convert all or any part of such
holder's shares of Series J Preferred Stock into fully paid and nonassessable
shares of Common Stock at the rate of one (1) share of Common Stock for each
share of Series J 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 J 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 J 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 J 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 J Preferred Stock shall receive, upon the conversion
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 J 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.


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        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"), and the
liquidation preference of the Series I Preferred Stock in the amount of $4.19
per share plus any declared but unpaid dividends (the "Series I 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 J Preferred Stock unless, prior thereto, the holders
of shares of Series J Preferred Stock shall have received an amount equal to
$2.98 per share of Series J Preferred Stock plus any declared but unpaid
dividends ("Series J 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 and the liquidation preferences of all other series of Preferred
Stock, if any, which rank on a parity with the Series J 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 J 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 J
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 J Preferred Stock without
the affirmative vote of the holders of a majority or more of the outstanding
shares of Series J Preferred Stock, voting separately as a class.


        Section 9.  Fractional Shares.  Series J 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 J 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, 1996.



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



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




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