I do have a slight problem on Win7 64 in CoD4 MP, not really a big deal but figured I should point it out. As soon as I join an MP server and the map loads, just before I come to the menu to select a side/weapon, I can hear the first few gunshots the the connection sort of drops, along with some artifacts leading to a black screen, sound jams at the time too, takes like 4 seconds, gets to the menu with a lot of "Connection Interrupted" signs. Other than that in this specific game I haven't found anything else.
Aside from that I have tried Company of Heroes with no flaw whatsoever too.
The artifacts during light usage might have also been my fault, in my biosmod the 2d and 3D Low are set to 100/100, 100/150 clocks, so I think it's because it's way too low.