Okay so I have tried playing a large number of the games that I played on vista before I upgraded to Windows 7 professional 64 bit. All the games install fine with no problems but when I actually start them they all start then stop, start and stop over and over again. I can ctrl+alt+delete my way to any of the main menus and get into an actual game play screen and it continues doing the same thing over and over and over again its starting to upset me a bit. The games I have tried are L4D, Supcom, UT3, and Roller Tycoon 3 (the list is longer than this but these are the 4 ones I have tried fixing myself). I have tried running them all in compatibility mode for Windows Vista where they all worked fine and I get the same issues every time. I'm currently running a core2duo E7300 at 2.66 ghz 4gigs of 1066 mhz of ram a 500gig hd with a 1000 watt thermaltake psu and a 6800gtx taking the place of a 9800gt while im waiting for an rma all on a gigabyte ep45-ud3p mobo. I don't know what could be causing this atm its boggling my mind. Any help?