I've noticed the following:
- * the problem only seems to happen in Windows 7, not in Linux; I assume this means the problem isn't the hardware;
* the problem never happens when I'm actually using the computer;
* it's definitely not a power option to turn the computer off after it's been idle for a certain period; it doesn't seem to be some scheduled task that might turn the computer off;
* the computer shuts down, but the case fan keeps spinning;
* the event log shows only this: The system has rebooted without cleanly shutting down first. This error could be caused if the system stopped responding, crashed, or lost power unexpectedly;
* it doesn't seem to be caused by overheating or a similar problem;
* there's no memory dump;
* there doesn't seem to be a specific delay before the computer shuts down, and it doesn't seem to shut down at a specific time.
Any hints about this problem?