I'm at my wit's end. Please help:

1. Using Win 98, I shut down the pc normally.
2. I see and hear everything turn off. (drives and fans wind down,
screen goes black. etc.)
3. At midnight (12:00 AM) the computer comes on all by itself.

I have disabled the Windows task manager. I've checked the BIOS to see
if there are any settings that look like they could do something like
this. I've updated the BIOS to the most recent version available. I've
done all I can think of except to throw it out the window. (That's next
unless someone here can help.)

Please do what you can.