WIN7 x64 hangs at shutdown.

Hi all, i've recently done a fresh install inc SP1 of win 7Pro x64 and now the pc almost constantly hangs on shutdown. everythings up to date driver wise etc. I was aware of this problem on my older quadcore machine but had it very infrequently, this happens almost constantly on my new one. Found a hotfix which i tried to install but had a warning say that "not applicable to my...