Girlfriend's computer shuts down by itself, please help

I gave my girfriend my old computer. Win 98, Pentium, 64M Ram. She told me
that it has been shutting itself down: she gets the "It is now safe to
shutdown your computer" screen, then shuts off, although she was playing
games or just only had the computer and monitor running with her Desktop
onscreen. It is doing the exact same thing if she had went to Star/Shut
Down and turned it off that way.

It has done this several times, at different times and different lengths of
time; it is intermittent, and driving her nuts!

Her computer is NOT connected to the internet, and she has not put any
strange disks in her computer, so I can rule out a virus or worm. Is there
some sort of 'automatic shutdown' setting somewhere that I am unaware of?

I'd appfreciate any help I can get. THANKS!!!!

***
"The music may be lousy, but at least it drowns out the dialogue."
---Crow T. Robot, MST3K, 'The Wild World of Batwoman'

"I don't trust anything that bleeds for 5 days and doesn't die."
---South Park, Bigger, Longer, and Uncut





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