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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 the 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-14 and 15d-14) for the registrant
          and have:

          a.)  designed such disclosure controls and procedures 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 as of a date within 90 days prior to the
               filing date of this quarterly report (the "Evaluation Date"); and

          c.)  presented in this quarterly report our conclusions about the
               effectiveness of the disclosure controls and procedures based on
               our evaluation as of the Evaluation Date;

     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 in the design or operation of
               internal controls which could adversely affect the registrant's
               ability to record, process, summarize and report financial data
               and have identified for the registrant's auditors any material
               weaknesses in internal controls; 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; and

     6.   The registrant's other certifying officers and I have indicated in
          this quarterly report whether there were significant changes in
          internal controls or other factors that could significantly affect
          internal controls subsequent to the date of our most recent
          evaluation, including any corrective actions with regard to
          significant deficiencies and material weaknesses.





Dated: November 12, 2004                            /s/ Brian A. Byrne
                                                    ----------------------------
                                                    Brian A. Byrne
                                                    Chief Financial Officer








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