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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.

     6.   The Company is a non-accelerated filer for the purposes of compliance
          with Securities and Exchange Commission rules under the Securities
          Exchange Act of 1934 that were adopted, pursuant to Section 404 of the
          Sarbanes-Oxley Act. Accordingly, the Company will not be subject to
          the requirements of Section 404 of the Sarbanes-Oxley Act until its
          fiscal year ending December 31, 2006.

     7.   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: August 12, 2005                  /s/ Brian A. Byrne
                                        ----------------------------------------
                                        Brian A. Byrne
                                        Chief Financial Officer


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