SECURITIES AND EXCHANGE COMMISSION
                              WASHINGTON, DC 20549
                              ___________________

                                  SCHEDULE 13G
                                 (Rule 13d-102)

            INFORMATION TO BE INCLUDED IN STATEMENTS FILED PURSUANT
                 TO RULES 13d-1(b), (c) AND (d) AND AMENDMENTS
                    THERETO FILED PURSUANT TO RULE 13d-2(b)
                             (Amendment No. 1)/1/



                        Integrated Circuit Systems, Inc.
--------------------------------------------------------------------------------
                               (Name of Issuer)

                    Common Stock, par value $0.01 per share
--------------------------------------------------------------------------------
                         (Title of Class of Securities)

                                  45811K 20 8
--------------------------------------------------------------------------------
                                 (CUSIP Number)

                               December 31, 2000
--------------------------------------------------------------------------------
            (Date of Event which Requires Filing of this Statement)


Check the appropriate box to designate the rule pursuant to which this Schedule
is filed:

[_] Rule 13d-1(b)
-----------------
[_] Rule 13d-1(c)
-----------------
[X] Rule 13d-1(d)
-----------------


                              __________________

                              Page 1 of 10 Pages

_______________

   /1/ The remainder of this cover page shall be filled out for a reporting
person's initial filing on this form with respect to the subject class of
securities, and for any subsequent amendment containing information which would
alter disclosures provided in a prior cover page.

   The information required in the remainder of this cover page shall not be
deemed to be "filed" for the purpose of Section 18 of the Securities Exchange
Act of 1934 ("Act") or otherwise subject to the liabilities of that section of
the Act but shall be subject to all other provisions of the Act (however, see
the Notes).


  CUSIP NO.  4581                        13G               Page 2 of 10 Pages


------------------------------------------------------------------------------
      NAMES OF REPORTING PERSONS.
 1
      ICST Acquisition Corp.

      I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY).
------------------------------------------------------------------------------
      CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)
 2                                                              (a) [X]
                                                                (b) [_]

------------------------------------------------------------------------------
      SEC USE ONLY
 3


------------------------------------------------------------------------------
      CITIZENSHIP OR PLACE OF ORGANIZATION
 4
      Delaware

------------------------------------------------------------------------------
                          SOLE VOTING POWER
                     5
     NUMBER OF

      SHARES       -----------------------------------------------------------
                          SHARED VOTING POWER
   BENEFICIALLY      6

     OWNED BY             9,095,265 (see Item 4)
                   -----------------------------------------------------------
       EACH               SOLE DISPOSITIVE POWER
                     7
    REPORTING

      PERSON       -----------------------------------------------------------
                          SHARED DISPOSITIVE POWER
       WITH          8
                          9,095,265 (see Item 4)
------------------------------------------------------------------------------
      AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
 9
       9,095,265 (see Item 4)
------------------------------------------------------------------------------
      CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES
10    (SEE INSTRUCTIONS)
                                                                    [_]

------------------------------------------------------------------------------
      PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
11

      14.2%
------------------------------------------------------------------------------
      TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)
12
      CO

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


  CUSIP NO.  4581                        13G               Page 3 of 10 Pages


------------------------------------------------------------------------------
      NAMES OF REPORTING PERSONS.
 1
      Bear Stearns MB 1998-1999 Pre-Fund, LLC

      I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY).
------------------------------------------------------------------------------
      CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)
 2                                                              (a) [x]
                                                                (b) [_]

------------------------------------------------------------------------------
      SEC USE ONLY
 3


------------------------------------------------------------------------------
      CITIZENSHIP OR PLACE OF ORGANIZATION
 4
      Delaware

------------------------------------------------------------------------------
                          SOLE VOTING POWER
                     5
     NUMBER OF

      SHARES       -----------------------------------------------------------
                          SHARED VOTING POWER
   BENEFICIALLY      6

     OWNED BY             9,095,265 (see Item 4)
                   -----------------------------------------------------------
       EACH               SOLE DISPOSITIVE POWER
                     7
    REPORTING

      PERSON       -----------------------------------------------------------
                          SHARED DISPOSITIVE POWER
       WITH          8
                          9,095,265 (see Item 4)
------------------------------------------------------------------------------
      AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
 9
       9,095,265 (see Item 4)
------------------------------------------------------------------------------
      CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES
10    (SEE INSTRUCTIONS)
                                                                    [_]

------------------------------------------------------------------------------
      PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
11

      14.2%
------------------------------------------------------------------------------
      TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)
12
      00

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


  CUSIP NO.  4581                        13G               Page 4 of 10 Pages


------------------------------------------------------------------------------
      NAMES OF REPORTING PERSONS.
 1
      The Bear Stearns Companies Inc.

      I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY).
------------------------------------------------------------------------------
      CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)
 2                                                              (a) [X]
                                                                (b) [_]

------------------------------------------------------------------------------
      SEC USE ONLY
 3


------------------------------------------------------------------------------
      CITIZENSHIP OR PLACE OF ORGANIZATION
 4
      Delaware

------------------------------------------------------------------------------
                          SOLE VOTING POWER
                     5
     NUMBER OF

      SHARES       -----------------------------------------------------------
                          SHARED VOTING POWER
   BENEFICIALLY      6

     OWNED BY             9,095,265 (see Item 4)
                   -----------------------------------------------------------
       EACH               SOLE DISPOSITIVE POWER
                     7
    REPORTING

      PERSON       -----------------------------------------------------------
                          SHARED DISPOSITIVE POWER
       WITH          8
                          9,095,265 (see Item 4)
------------------------------------------------------------------------------
      AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
 9
       9,095,265 (see Item 4)
------------------------------------------------------------------------------
      CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES
10    (SEE INSTRUCTIONS)
                                                                    [_]

------------------------------------------------------------------------------
      PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
11

      14.2%
------------------------------------------------------------------------------
      TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)
12
      HC

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


SCHEDULE 13G


ITEM 1(A).     NAME OF ISSUER:

          Integrated Circuit Systems, Inc.

ITEM 1(B).     ADDRESS OF ISSUER'S PRINCIPAL EXECUTIVE OFFICES:

          2435 Boulevard of the Generals
          Norristown, PA  19403

ITEM 2(A).     NAME OF PERSON FILING:

               This Statement is being jointly filed by each of the following
          persons pursuant to Rule 13d-1(f) promulgated by the Securities and
          Exchange Commission pursuant to Section 13 of the Securities Exchange
          Act of 1934, as amended (the "Exchange Act"):

          (i)   ICST Acquisition Corp. ("Acquisition Sub"), a Delaware
                corporation, by virtue of its direct beneficial ownership of
                shares of common stock, par value $0.01 per share (the "Common
                Stock"), of the Issuer;

          (ii)  Bear Stearns MB 1998-1999 Pre-Fund, LLC (the "Pre-Fund"), a
                Delaware limited liability company, by virtue of its direct
                beneficial ownership of shares of Common of the Issuer; and

          (iii) The Bear Stearns Companies Inc. ("BSC"), a Delaware corporation,
                as the managing member of the Pre-Fund and sole stockholder of
                Acquisition Sub.

               Acquisition Sub, the Pre-Fund and BSC are collectively referred
          herein as the "Reporting Persons." The Reporting Persons have entered
          into a Joint Filing Agreement, a copy of which is filed with this
          statement as Exhibit A (which is incorporated herein by reference),
          pursuant to which the Reporting Persons have agreed to file this
          statement jointly in accordance with the provisions of Rule 13d-
          1(f)(1) under the Exchange Act.


                              Page 5 of 10 Pages


ITEM 2(B).     ADDRESS OF PRINCIPAL BUSINESS OFFICE OR, IF NONE, RESIDENCE:

               The address of the principal business office of each of the
          Reporting Persons is   The Bear Stearns Companies Inc., 245 Park
          Avenue, New York, New York 10167.


ITEM 2(C).     CITIZENSHIP:

               The Pre-Fund is a limited liability company organized under the
          laws of the State of Delaware, and BSC and Acquisition Sub each is a
          corporation organized under the laws of the State of Delaware.

ITEM 2(D).     TITLE OF CLASS OF SECURITIES:

          Common Stock, par value $0.01 per share.

ITEM 2(E). CUSIP NO.:

           45811K 20 8

ITEM 3.   IF THIS STATEMENT IS FILED PURSUANT TO RULES 13D-1(B), OR 13D-2(B) OR
          (C), CHECK WHETHER THE PERSON FILING IS:


          (a) [_] a broker or dealer registered under section 15 of the Act (15
                  U.S.C. 78o);
          (b) [_] a bank as defined in section 3(a)(6) of the Act
                  (15 U.S.C. 78c);
          (c) [_] an insurance company as defined in section
                  3(a)(19) of the Act (15 U.S.C. 78c);
          (d) [_] an investment company registered under section 8 of the
                  Investment Company Act of 1940 (15 U.S.C. 80a-8);
          (e) [_] an investment adviser in accordance with
                  (S)240.13d-1(b)(1)(ii)(E);
          (f) [_] an employee benefit plan or
                  endowment fund in accordance with (S)240.13d-1(b)(1)(ii)(F);
          (g) [_] a parent holding company or control person in accordance with
                  (S) 240.13d-1(b)(1)(ii)(G);
          (h) [_] a savings associations as defined in Section
                  3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813);


                              Page 6 of 10 Pages


          (i) [_] a church plan that is excluded from the definition of an
                  investment company under section 3(c)(14) of the Investment
                  Company Act of 1940 (15 U.S.C. 80a-3); or

          (j) [_] a Group, in accordance with (S)240.13d-
                  1(b)(1)(ii)(J). Not applicable.


ITEM 4.   OWNERSHIP.

          (A)-(C). Each Reporting Person named in response to Item 2 hereof has,
          as of December 31, 2000, shared power to vote or to direct the vote
          and shared power to dispose or to direct the disposition of the Common
          Stock as follows:

          (i)   As of the date thereof, Acquisition Sub has shared power to vote
                and to dispose of 9,095,265 shares of Common Stock, representing
                approximately 14.2% of the outstanding Common Stock issued and
                outstanding as of February 14, 2001, as reported in the Issuer's
                Quarterly Report on Form 10-Q for the quarterly period ended
                September 30, 2000 (the "Quarterly Report").

          (ii)  As of the date hereof, the Pre-Fund has shared power to vote and
                to dispose of 9,095,265 shares of Common Stock to which it has a
                current right, representing approximately 14.2% of the total
                number of outstanding shares of Common Stock as reported in the
                Quarterly Report.

          (iii) BSC, as the managing member of the Pre-Fund and sole shareholder
                of Acquisition Sub, may be deemed to share voting and
                dispositive power with respect to 9,095,265 shares of Common
                Stock currently held by the Pre-Fund and Acquisition Sub,
                representing approximately 14.2% of the total number of
                outstanding shares of Common Stock as reported in the Quarterly
                Report. The filing of this Statement by BSC shall not be
                construed as an admission that BSC is, for the purpose of
                Section 13(d) of the Exchange Act, the beneficial owner of such
                shares held by the Pre-Fund and Acquisition Sub.

ITEM 5.   OWNERSHIP OF FIVE PERCENT OR LESS OF A CLASS.

          If this statement is being filed to report the fact that as of the
          date hereof each of the Reporting Persons has ceased to be the
          beneficial owner of more than five percent of the class of securities,
          check the following  [_].


                              Page 7 of 10 Pages


ITEM 6.   OWNERSHIP OF MORE THAN FIVE PERCENT ON BEHALF OF ANOTHER PERSON.

          Not applicable.

ITEM 7.   IDENTIFICATION AND CLASSIFICATION OF THE SUBSIDIARY WHICH ACQUIRED THE
          SECURITY BEING REPORTED ON BY THE PARENT HOLDING COMPANY OR CONTROL
          PERSON.

          Not applicable.

ITEM 8.   IDENTIFICATION AND CLASSIFICATION OF MEMBERS OF THE GROUP.

          Not applicable.

ITEM 9.   NOTICE OF DISSOLUTION OF GROUP.

          Not applicable.

ITEM 10.  CERTIFICATIONS.

          Not applicable.


                              Page 8 of 10 Pages


                                   SIGNATURE

          After reasonable inquiry and to the best of our knowledge and belief,
the undersigned certify that the information set forth in this statement is
true, complete and correct.


Date: April 10, 2001

                                       BEAR STEARNS MB 1998-1999 PRE-FUND, LLC

                                       By:  The Bear Stearns Companies Inc.

                                       By: /s/ Mark E. Lehman
                                          __________________________________
                                          Name:  Mark E. Lehman
                                          Title: Executive Vice President


                                      THE BEAR STEARNS COMPANIES INC.

                                       By: /s/ Mark E. Lehman
                                          __________________________________
                                          Name:  Mark E. Lehman
                                          Title: Executive Vice President


                                      ICST ACQUISITION CORP.

                                       By: /s/ John D. Howard
                                          __________________________________
                                          Name:  John D. Howard
                                          Title: Executive Vice President




                              Page 9 of 10 Pages


                                                                       EXHIBIT A



                    AGREEMENT REGARDING THE JOINT FILING OF
                                  SCHEDULE 13G

                             _____________________


The undersigned hereby agree as follows:

          (i) Each of them is individually eligible to use the Schedule 13G to
which this Exhibit is attached, and such Schedule 13G is filed on behalf of each
of them; and

          (ii) each of them is responsible for the timely filing of such
Schedule 13G and any amendments thereto, and for the completeness and accuracy
of the information concerning such person contained therein; but none of them is
responsible for the completeness or accuracy of the information concerning the
other persons making the filing, unless such person knows or has reason to
believe that such information is inaccurate.

Date: April 10, 2001

                                      BEAR STEARNS MB 1998-1999 PRE-FUND, LLC

                                      By:  The Bear Stearns Companies Inc.

                                      By: /s/ Mark E. Lehman
                                         ------------------------------------
                                         Name:  Mark E. Lehman
                                         Title: Executive Vice President


                                      THE BEAR STEARNS COMPANIES INC.

                                      By: /s/ Mark E. Lehman
                                         ------------------------------------
                                         Name:  Mark E. Lehman
                                         Title: Executive Vice President


                                      ICST ACQUISITION CORP.

                                      By: /s/ John D. Howard
                                         ------------------------------------
                                         Name:  John D. Howard
                                         Title: Executive Vice President




                              Page 10 of 10 Pages