[kmeade]

I'm a frequent sleeper and I depend on the feature. Next time your machine wakes up by itself, go to a DOS prompt and type "powercfg -lastwake" That will tell you how it happened.

For me, part of the solution was to go into the device manager and edit the properties for my mouse and my network controller. On the "power management" tab I disabled the "allow this device to wake up the computer" option. I only use the keyboard to wake the PC.

Additionally, when I left the machine sleeping overnight, there was some scheduled task that would occasionally wake the machine. There is a way to disable that, but I forget the specifics.

[nfriedly]

Cool, I'll try that sometime. I'm traveling for the next couple of weeks, so it'll be too late to report back here, but thanks in advance.

I really wouldn't be bothered by occasional wakeups if it would go back to sleep afterwards...

[gambiting]

My computer does it, and typing in powercfg -lastwake just says "unknown source". I've disabled every wake event, update service, wake-on-lan, disabled the ability of my mouse and keyboard to wake my computer up, and it still does it.

[saahtb]

VirtualBox for example uses something called "wake timers" that wake up the machine right after it goes to sleep.