Follow this link it should help you.
http://exchange.ni.com/servlet/ProcessRequest?RHIVEID=101&RPAGEID=135&HOID=506500000008000000A38F0000&UCATEGORY_0=_49_%24_6_&UCATEGORY_S=0&USEARCHCONTEXT_TIER_0=0&USEARCHCONTEXT_TIER_S=0&USEARCHCONTEXT_QUESTION_0=moitor+cpu+usage&USEARCHCONTEXT_QUESTION_S=0
Joe.
"NOTHING IS EVER EASY"