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                                                                     EXHIBIT 3.4

                            CERTIFICATE OF AMENDMENT
                                       TO
                          CERTIFICATE OF DESIGNATIONS
                                       OF
                      SERIES A CONVERTIBLE PREFERRED STOCK
                                       OF
                              QUALMARK CORPORATION


     QUALMARK CORPORATION (the "Corporation"), a Colorado corporation duly
organized and existing under the Colorado Business Corporation Act, does hereby
certify that the following resolutions were adopted by the Board of Directors of
the Corporation at a meeting duly called and held on April 20, 2001:

     WHEREAS, the Board of Directors filed a Certificate of Designations on
September 2, 1999, designating 502,326 shares of Series A Convertible Preferred
Stock; and

     WHEREAS, the Board deems it is in the best interest of the Corporation to
increase the number of shares designated as Series A Convertible Preferred
Stock, and it is therefore,

     RESOLVED, that the number of shares designated as Series A Convertible
     Preferred Stock be increased to 692,951 shares and the introductory
     resolution of the Certificate of Designations filed by the Corporation with
     the Secretary of State of Colorado on September 2, 1999, is hereby amended
     to read as follows:

          "RESOLVED, that, pursuant to the authority expressly granted to and
          vested in the Board of Directors of the Corporation in accordance with
          the provisions of its Articles of Incorporation, a series of Preferred
          Stock of the Corporation be and hereby is established, consisting of
          692,951 shares, no par value per share, to be designated the "Series
          A Convertible Preferred Stock" (hereinafter, "Series A Preferred
          Stock"); that the Board of Directors be and hereby is authorized to
          issue such shares of Series A Preferred Stock from time to time and
          for such consideration and on such term as the Board of Directors
          shall determine; and that, subject to the limitations provided by law
          and by the Articles of Incorporation, the voting powers, preferences
          and relative, participating, optional and other rights, and
          qualifications, limitations and restrictions thereof shall be as
          follows:"

     FURTHER RESOLVED, that all of the other provisions of said Certificate of
     Designation shall remain in full force and effect.

     Dated: April 30, 2001

                                        QUALMARK CORPORATION

                                        By: /s/    Charles D. Johnston
                                           -------------------------------------
                                            Charles D. Johnston
                                            President and CEO

STATE OF COLORADO)
                 ) ss
COUNTY OF ADAMS  )

     Subscribed and sworn to before me this 30 day of April, 2001, by Charles
Johnston, who is Corporate Secretary of QualMark Corporation.

     Witness my hand and official seal.

     My commission expires 4-19-2003.       /s/    Patricia L. Weeks
                                           -------------------------------------
                                             Notary Public

          [NOTARY PUBLIC SEAL - PATRICIA L. WEEKS - STATE OF COLORADO]