So I've had Windows 7 x64 running on my i5 imac for a few days now and everything is smooth as butter with the exception of sleeping the display or sleeping the entire system. I've done countless searches on this forum and any mac/windows forum I could find but it yielded no solution. Is anyone else having this issue? The imac refuses to go to sleep regardless of power settings and the screen saver does not work. Forcing the display to sleep with the program Instant Sleep does nothing. It simply turns black for a second and then turns back on. Any advice or solutions would be greatly appreciated! Thank you. Edit: Problem solved thanks to Crb! See post # 22 for solution.