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                                                                     Exhibit 5.5


                              EMPLOYMENT AGREEMENT

      This Employment Agreement (the "Agreement") is made as of the 13th day of
July, 1998, by and between Fluent, Inc., a New Hampshire Corporation with its
principal place of business at 10 Cavendish Court, Lebanon, New Hampshire, 03766
(the "Company"), and Peter L. Christie of 5 Sugar Maple Lane, Etna, New
Hampshire 03750 (the "Executive").

                                   BACKGROUND

      The Company desires to engage Executive to provide financial, business and
industry expertise in a variety of areas to assist the Company in its business
of developing, marketing, selling and supporting computational fluid dynamics
software. The Executive is willing to apply his financial, business and industry
expertise on a full time basis for the benefit of the Company. Accordingly, the
Company and Executive wish to set forth the terms of their agreement as follows.

      1. EMPLOYMENT. The Company offers and the Executive accepts full time
      employment as Vice President and Chief Financial Officer for the Company.
      The Executive shall report to the President of the Company, and shall have
      all powers and duties as would normally be associated with the position of
      Vice President and Chief Financial Officer. The Executive shall also
      perform such other duties as may reasonably be requested from time to time
      by the President of the Company. The Executive shall work at the Company's
      facility in Lebanon, New Hampshire or at such other place or places as the
      Company may reasonably request.

      2. TERM and COMMENCEMENT OF EMPLOYMENT. The initial term of employment
      under the Agreement shall begin as set forth herein and shall continue for
      a period of three (3) years (the "Term"), subject to prior termination in
      accordance with the terms hereof. Thereafter, the Agreement shall
      automatically renew for successive one year terms unless either party
      shall give the other ninety (90) days written notice prior to the end of
      any applicable term of its intent not to renew the Agreement. Executive's
      employment under the Agreement shall commence as soon as possible, but not
      later than August 17

      3. COMPENSATION.

      3.1. Base Salary. During the period of employment, the Executive will
      receive a minimum base salary of $105,000 per year payable in accordance
      with the Company's payroll procedures for its executives. The Company
      shall review Executive's base salary on an annual basis.

      3.2. Bonus. Executive shall be entitled to participate in the Company's
      Management Bonus Plan at Level 2, which for the purposes of ease of
      calculation, shall be determined from July 1, 1998. A copy of the plan is
      available from the Company. You will also be entitled to participate in
      the Company's profit-sharing plan.

      3.3. Stock Options. By separate agreement you will receive a grant of
      10,000 option shares of Aavid Thermal Technologies, Inc. common stock
      subject to vesting based on an exercise price set on or about August 1,
      1998. Vesting shall be over 3 years, with one-fourth vesting annually
      commencing on the date of the grant of the options.

      3.4. Benefits. The Executive shall receive medical and other benefits as
      provided to other executives from time to time. The Executive shall be
      entitled to four weeks of paid vacation per year, and shall qualify for
      the 401(k) Plan as of July 1, 1998.


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      3.5. Expenses and Facilities. The Company shall reimburse the Executive
      for reasonable out-of-pocket expenses incurred in fulfilling his duties.
      The Company shall, within its financial means and constraints, provide the
      Executive with suitable office facilities, equipment, supplies and staff.

      3.6. One-Time Payment. Upon commencement of Executive's employment, the
      Company shall make a one-time payment to Executive in the amount of
      $15,000.00.

      4. TERMINATION.

      4.1. For Cause. For purposes of this agreement, "for cause" shall include:
      (a) embezzlement, fraud, or other acts of dishonesty; (b) material breach
      by Executive of any of his obligations under this Agreement; (c)
      conviction or entrance of a plea of guilty or nolo contendre to a felony
      or other crime; or (d) conduct involving moral turpitude. Upon termination
      for cause, the Company's sole and exclusive obligation will be to pay the
      Executive his compensation earned through the date of termination, and the
      Executive shall not be entitled to any compensation after the date of
      termination.

      4.2. Upon Death or Disability. In the event of the Executive's death or
      total disability during the term of this Agreement, the Company's sole and
      exclusive obligation will be to pay to the Executive, if disabled, or to
      his estate, if deceased, the Executive's compensation earned through the
      date of death or disability. The Executive shall be deemed to be totally
      disabled if he is unable to perform his duties under this Agreement by
      reason of mental or physical illness or accident for a period of three
      consecutive months.

      5. COVENANT NOT TO COMPETE.

      5.1. Covenant. While the Executive continues to be employed by the
      Company, and for a one year period after termination of employment, for
      any reason, the Executive will not directly or indirectly:

      5.1.1. Enter into or attempt the "Restricted Business" as defined in
             Exhibit A attached hereto.

      5.1.2. Induce or attempt to persuade any former, current or future
             employee or other participant in the Company's business to
             terminate such employment or other relationship in order to enter
             into any relationship with the Executive, any business organization
             in which the Executive is a participant in, or any other business
             organization in competition with the Company's business.

      6. CONFIDENTIALITY. The Executive acknowledges that he will develop and be
      exposed to information that is or will be confidential and proprietary to
      the Company. The information includes, but is not limited to, customer
      lists, marketing plans, price data, product plans, financial information,
      software, trade secrets, and other intangible information. Such
      information shall be deemed confidential to the extent not generally known
      within the trade. The Executive agrees, during the term of the Agreement
      and thereafter, to make use of such information only in the performance of
      his duties under this Agreement, to maintain such information in
      confidence and to disclose the information only to persons with a need to
      know as determined by the Company.

      7. SEVERABILITY. If, in any judicial proceeding, a court of competent
      jurisdiction shall refuse to enforce any separate covenants deemed
      included in this Agreement, or shall find that the


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      term or geographic scope of one or more of the separate covenants is
      unreasonably broad, then the court shall modify the provision to the
      minimum extent necessary to permit enforcement, and the remainder of this
      Agreement shall not be affected thereby.

      8. REMEDIES. The Executive acknowledges that monetary damages would be
      inadequate to compensate the Company for any breach by the Executive of
      the covenants set forth in Sections 5 and 6 above. The Executive agrees
      that, in addition to other remedies which may be available, the Company
      shall be entitled to obtain injunctive relief against the threatened
      breach of this Agreement or the continuation of any breach, or both,
      without the necessity of proving actual damages.

      9. NOTICES. Any notices permitted or required under this Agreement shall
      be deemed given upon the date of personal delivery or forty-eight (48)
      hours after deposit in the United States mail, postage fully prepaid,
      return receipt requested, to the address set forth in the first paragraph
      or at any other address as any party may, from time to time, designate by
      notice given in compliance with this Section.

      10. MISCELLANEOUS. This Agreement shall be governed by and constructed in
      accordance with the laws of the state of New Hampshire, and contains the
      entire understanding between the parties, and supersedes any prior
      understandings and agreements among them. Further, this Agreement shall be
      binding upon the heirs, executors, administrators, successors and assigns
      of the parties hereto, and the waiver by the Company of any breach of this
      Agreement by Executive shall not act as a waiver of any subsequent break
      by the Executive.

      11. OTHER AGREEMENTS. Executive represents and warrants to Company that he
      is not bound by agreements with other entities, including non-competition
      and non-disclosure agreements.

      12. SEPARATE COUNSEL. The parties acknowledge that the Company has been
      represented in this transaction by its General Counsel, that the Executive
      has not been represented in this transaction by the Company's attorneys,
      and the Executive has been advised that it is important for him to seek
      separate legal advice and representation in this matter.

Date:  July 13, 1998
Fluent, Inc.
a New Hampshire Corporation                     Peter L. Christie



By: Bharatan R. Patel                           /s/ Peter L. Christie
Its:  President                                      Executive


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                                    EXHIBIT A

                               RESTRICTED BUSINESS

      The "Restricted Business" shall include the development, marketing, sale
and distribution of computational fluid dynamics software, and shall include the
geographic areas of North America, Europe and Asia.


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