Computer Starts Up On It's Own

beachbuoy said:

My Win7 64-bit PC, built on a Gigabyte P55A mainboard, starts up all by itself. Not every time I shut it off. But, maybe 30-40 percent of the time, I will shut it down for the night and, if I don't flip the power supply off, the computer will start up sometime during the night and be running when I walk into the office in the (home) office. Once, I caught it in action. I came back to the computer about 30 minutes after shutting down Windows and it started booting back up as I was walking into the room.

Possibly related, if I put the PC into Sleep mode, I will come back later to find a blank screen with only the cursor blinking in the upper left corner of the screen, apparently failing to "Resume." I say apparently, because the only way to get Windows back up is to kill the power and reboot. Upon rebooting, it stops at the boot option screen asking if I want to wipe the resume info and start fresh or not. If I don't wipe and start fresh, it goes back to the blinking cursor and a blank screen.

I don't even know where to start in looking for an answer to this puzzle. Any ideas?

This indeed is rather strange. The most logical thing would be that your house is haunted :), no just kidding. == I googled "windows 7 pc starts unexpectedly" and surprisingly there are a lot of links. One of them should be your problem. Sorry I did not have anything more specific.

If the PC is in sleep mode, it can restart from an external interrupt it is getting - unless you have ruled that out with your settings.

If the power is off, it should not be able to restart.

If you get it again after it starts up go to an admin command prompt and put "powercfg lastwake". It will tell you what did it if it can tell.
Lastwake Command