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                                                                    Exhibit 31.2

                      CERTIFICATION AS ADOPTED PURSUANT TO
                  SECTION 302 OF THE SARBANES-OXLEY ACT OF 2002

I, Brian A. Byrne, certify that:

      1.    I have reviewed this quarterly report on Form 10-Q of Aavid Thermal
            Technologies, Inc.

      2.    Based on my knowledge, this quarterly report does not contain any
            untrue statement of a material fact or omit to state a material fact
            necessary to make the statements made, in light of the circumstances
            under which such statements were made, not misleading with respect
            to the period covered by this quarterly report;

      3.    Based on my knowledge, the financial statements, and other financial
            information included in this quarterly report, fairly present in all
            material respects the financial condition, results of operation and
            cash flows of the registrant as of, and for, the periods presented
            in this quarterly report;

      4.    The registrant's other certifying officers and I are responsible for
            establishing and maintaining disclosure controls and procedures (as
            defined in Exchange Act Rules 13a-5(f) and 15d-5(f) for the
            registrant and have:

            a.)   designed such disclosure controls and procedures, or caused
                  such disclosure controls and procedures to be designed under
                  our supervision, to ensure that material information relating
                  to the registrant, including its consolidated subsidiaries, is
                  made known to us by others within those entities, particularly
                  during the period in which this quarterly report is prepared;

            b.)   evaluated the effectiveness of the registrant's disclosure
                  controls and procedures and presented in this report our
                  conclusions about the effectiveness of the disclosure controls
                  and procedures, as of the end of the period covered by this
                  report based on such evaluation; and

            c.)   disclosed in this report any change in the registrant's
                  internal control over financial reporting that occurred during
                  the registrant's fiscal quarter covered by this report that
                  has materially affected, or is reasonably likely to materially
                  affect, the registrant's internal control over financial
                  reporting; and

      5.    The registrant's other certifying officers and I have disclosed,
            based on our most recent evaluation, to the registrant's auditors
            and the audit committee of the registrant's Board of Directors (or
            persons performing equivalent functions):

            a.)   all significant deficiencies and material weaknesses in the
                  design or operation of internal control over financial
                  reporting which are reasonably likely to adversely affect the
                  registrant's ability to record, process, summarize and report
                  financial information; and

            b.)   any fraud, whether or not material, that involves management
                  or other employees who have a significant role in the
                  registrant's internal controls

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