EXHIBIT 99.3

                          AAVID THERMAL TECHNOLOGIES, INC.
               INSTRUCTION TO REGISTERED HOLDER AND/OR DEPOSITORY
                TRUST COMPANY PARTICIPANT FROM BENEFICIAL OWNER
                                      FOR
                             OFFER TO EXCHANGE ITS
                   12 3/4% SENIOR SUBORDINATED NOTES DUE 2007
              WHICH HAVE BEEN REGISTERED UNDER THE SECURITIES ACT
                       FOR ANY AND ALL OF ITS OUTSTANDING
                   12 3/4% SENIOR SUBORDINATED NOTES DUE 2007
                   THAT WERE ISSUED AND SOLD IN A TRANSACTION
                       EXEMPT FROM REGISTRATION UNDER THE
                       SECURITIES ACT OF 1933, AS AMENDED

THE EXCHANGE OFFER WILL EXPIRE AT 5:00 P.M., NEW YORK CITY TIME, ON
            , 2000, UNLESS THE OFFER IS EXTENDED. TENDERS MAY BE WITHDRAWN PRIOR
TO 5:00 P.M., NEW YORK CITY TIME, ON THE EXPIRATION DATE.

To Registered Holder and/or Depository Trust Company Participant:

    The undersigned hereby acknowledges receipt of the Prospectus dated
            , 2000 (the "Prospectus") of Aavid Thermal Technologies, Inc., a
Delaware corporation (the "Company"), and the accompanying Letter of Transmittal
(the "Letter of Transmittal"), that together constitute the Company's offer (the
"Exchange Offer") to exchange its 12 3/4% Senior Subordinated Notes due 2007
(the "Exchange Notes"), which have been registered under the Securities Act of
1933, as amended (the "Securities Act"), for all of its outstanding 12 3/4%
Senior Subordinated Notes due 2007 (the "Outstanding Notes"). Capitalized terms
used but not defined herein have the meanings ascribed to them in the
Prospectus.

    This will instruct you, the registered holder and/or Depository Trust
Company Participant, as to the action to be taken by you relating to the
Exchange Offer with respect to the Outstanding Notes held by you for the account
of the undersigned.

    The aggregate face amount of the Outstanding Notes held by you for the
account of the undersigned is (FILL IN AMOUNT):

        $____________ of the 12 3/4% Senior Subordinated Notes due 2007.

    With respect to the Exchange Offer, the undersigned hereby instructs you
(CHECK APPROPRIATE BOX):

       / /  To TENDER the following Outstanding Notes held by you for the
           account of the undersigned (INSERT PRINCIPAL AMOUNT OF OUTSTANDING
           NOTES TO BE TENDERED (IF LESS THAN ALL)):

          $____________

       / /  NOT to TENDER any Outstanding Notes held by you for the account of
           the undersigned.

    If the undersigned instructs you to tender the Outstanding Notes held by you
for the account of the undersigned, it is understood that you are authorized to
make, on behalf of the undersigned (and the undersigned, by its signature below,
hereby makes to you), the representations and warranties contained in the Letter
of Transmittal that are to be made with respect to the undersigned as a
beneficial owner, including but not limited to the representations, that
(i) the undersigned is not an "affiliate" of the Company, (ii) any Exchange
Notes to be received by the undersigned are being acquired in the ordinary
course of its business, (iii) the undersigned has no arrangement or
understanding with any person to participate in a distribution (within the
meaning of the Securities Act) of Exchange Notes to be received in the Exchange
Notes, and (iv) if the undersigned is not a broker-dealer, the undersigned is
not engaged in, and does not intend to engage in, a distribution (within the
meaning of the Securities Act) of such

Exchange Notes. The Company may require the undersigned, as a condition to the
undersigned's eligibility to participate in the Exchange Offer, to furnish to
the Company (or an agent thereof) in writing information as to the number of
"beneficial owners" within the meaning of Rule 13d-3 under the Exchange Act on
behalf of whom the undersigned holds the Outstanding Notes to be exchanged in
the Exchange Offer. If the undersigned is a broker-dealer that will receive
Exchange Notes for its own account in exchange for Outstanding Notes, it
represents that the Outstanding Notes to be exchanged for Exchange Notes were
acquired by it as a result of market-making activities or other trading
activities and acknowledges that it will deliver a prospectus in connection with
any resale of such Exchange Notes; however, by so acknowledging and by
delivering a prospectus, the undersigned will not be deemed to admit that it is
an "underwriter" within the meaning of the Securities Act.

                                   SIGN HERE

________________________________________________________________________________
NAME OF BENEFICIAL OWNER(S)

________________________________________________________________________________

________________________________________________________________________________
SIGNATURE

________________________________________________________________________________

________________________________________________________________________________
NAME(S) (PLEASE PRINT)

________________________________________________________________________________

________________________________________________________________________________
(ADDRESS)

________________________________________________________________________________
(TELEPHONE NUMBER)

________________________________________________________________________________
(TAXPAYER IDENTIFICATION OR SOCIAL SECURITY NUMBER)

________________________________________________________________________________
DATE

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