If it's IIS, there are a couple things that we have run into.
If there is any 32 bit code, IIS can't address memory. Re-starting it worked. Getting rid of the 32 bit code worked better!
Re-cycling the app pools may also need to be looked at. Depending upon the connections, when a recycle occurred, CPU went through the roof.
Michael L John
If you assassinate a DBA, would you pull a trigger?
To properly post on a forum:
http://www.sqlservercentral.com/articles/61537/