I'm having a problem with the sleep functionality. When Vista puts my machine to sleep, I don't believe it actually accomplishes actual "sleep". All of my USB devices are disabled and the display is turned off, but the fans (CPU and case) are still running and neither my power button nor my reset button have any affect on waking the machine.

The only solution I've found is to hold down the power button for ~5 secs to force a power-down. When I turn the power back on, I get a loading screen that says "Resuming Windows" (or something similar), then I get a long black screen with a few flickers and a lot of hard drive thrashing. After ~2 mins of the flickering black screen, Vista tries to put the machine back to sleep. This is about 50% successful. Half of the time the machine actually achieves sleep, my green power LED blinks, and the machine returns to normal use after I press the power button. The other half of the time, I get put back into the "almost-sleep" state and I have to force a power-down again.