Windows Does Not Start After Sleep[2]=Power Management
After wake problem check the event viewer for additional information
Just type that term in search
Take the memory diagnostic test
Again just type that term in search.
If these suggestions do not lead to a solution. It is due to a conflict, I would try a clean boot to uncover the problem.
http://support.microsoft.com/kb/929135
This may lead you to the source of the conflict.