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                                                                    Exhibit 32.1

                CERTIFICATION PURSUANT TO 18 U.S.C SECTION 1350,
                             AS ADOPTED PURSUANT TO
                  SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

            In connection with the Quarterly Report on Form 10-Q of Aavid
Thermal Technologies, Inc. (the "Company") for the quarter ended September 30,
2005 as filed with the Securities and Exchange Commission on the date hereof
(the "Report"), the undersigned officers of the Company, hereby certify, to
their knowledge, that:

      1.    the Report fully complies with the requirements of Section 13(a) or
            15(d), as applicable, of the Securities and Exchange Act of 1934;
            and

      2.    the information contained in the Report fairly presents, in all
            material respects, the financial condition and results of operations
            of the Company.

Dated: November 14, 2005         /s/ Bharatan R. Patel
                                 -----------------------------------------------
                                 Bharatan R. Patel
                                 Chairman, President and Chief Executive Officer


Dated: November 14, 2005         /s/ Brian A. Byrne
                                 -----------------------------------------------
                                 Brian A. Byrne
                                 Vice President and Chief Financial Officer






