ADAPTEC INC
EXHIBIT 10.05
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<BR></FONT><FONT SIZE=2><B>Exhibit 10.05    <BR>    </B></FONT></P>

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<BR></FONT><FONT SIZE=2><B>ADAPTEC,&nbsp;INC.<BR>  <BR>    Adaptec Variable Incentive Plan<BR>  <BR>    November&nbsp;1, 2004    <BR>    </B></FONT></P>

<P><FONT SIZE=2><B>1.&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Plan Name  </B></FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;The name of the plan is the Variable Incentive Plan (the "Plan") of Adaptec,&nbsp;Inc. (the "Company"). </FONT></P>

<P><FONT SIZE=2><B>2.&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Purpose  </B></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;The purpose of the Plan is to provide a direct financial incentive for eligible employees in order to assist the Company's stockholders realize increased value
from their investment. </FONT></P>

<P><FONT SIZE=2><B>3.&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Eligibility  </B></FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Full-time employees, as designated by the Company, are eligible to participate in the Plan ("Participants"). </FONT></P>

<P><FONT SIZE=2><B>4.&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Funding of the Plan  </B></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;The target award is 4% of each eligible employee's quarterly base salary. The actual award may be between 0 to 5% of an employee's quarterly base salary. </FONT></P>

<P><FONT SIZE=2><B>5.&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Plan Payments  </B></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Payment of awards under the Plan for non-Section&nbsp;16 Officers will be determined in the sole discretion of the Company's Chief Executive
Officer. Payments of awards under the Plan for Section&nbsp;16 Officers will be determined in the sole discretion of the Compensation Committee after consultation with the Company's Chief Executive
Officer, except in the case of an award payable to the Chief Executive Officer, which shall be determined in the sole discretion of the Compensation Committee. A Section&nbsp;16 Officer shall not be
entitled to receive any payment of an award until it is approved by the Compensation Committee. </FONT></P>

<P><FONT SIZE=2><B>6.&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Administration of the Plan  </B></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;The Plan, as it applies to Section&nbsp;16 Officers, shall be administered by the Compensation Committee of the Company. The Plan, as it applies to
Section&nbsp;16 Officers, shall be interpreted by the Compensation Committee in its sole discretion, which such determinations shall be final and binding on all Participants. </FONT></P>

<P><FONT SIZE=2><B>7.&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Source of Payments  </B></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;All payments shall be made from the general assets of the Company. </FONT></P>

<P><FONT SIZE=2><B>8.&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Governing Law  </B></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;The Plan shall be governed by the laws of the State of California. </FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2>1</FONT></P>

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<P><FONT SIZE=2><B>9.&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;No Right to Employment  </B></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Employees shall have no right to continued employment and shall be considered to be "at-will" employees of the Company. </FONT></P>

<P><FONT SIZE=2><B>10.&nbsp;&nbsp;&nbsp;Withholding  </B></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;The Company may withhold federal, state and local taxes in connection with any benefit realized by a Participant as a condition of making payment of any award
under the Plan. </FONT></P>

<P><FONT SIZE=2><B>11.&nbsp;&nbsp;&nbsp;Amendment or Termination of the Plan  </B></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;The Plan may be amended or terminated by the Chief Executive Officer with respect to all non-Section&nbsp;16 Officers and by the Board of Directors
of the Company or the Compensation Committee with respect to all Section&nbsp;16 Officers, in either case at any time without the consent of any Section&nbsp;16 Officer. </FONT></P>

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<FONT SIZE=2><A HREF="#toc_ki1603_1">Exhibit 10.05</A></FONT><BR>
<FONT SIZE=2><A HREF="#toc_ki1603_2">ADAPTEC, INC. Adaptec Variable Incentive Plan November 1, 2004</A></FONT><BR>

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