Hi, I had a very similar problem with a pc doing all sorts of weird and
wonderful things. As it was an old one, I began to give up with it, but all
it turned out to be was a dead (or dying) battery, and it needed ALOT of
cleaning inside.
It was one of those really annoying things, sometimes  it recognised things,
sometimes it didn't, and for some reason it began making all sorts of
strange noises.
It was (and still is) running win95, so that gives an idea of it's age.
Might I add, it had been standing for probably quite a long time before it
came into my possession.
Point is, I didn't give up with it, and it's now working fine in my kids
bedroom for the time being.
Fires up perfectly everytime now.
In my case, it cost next to nothing, so I relied on trial and error. It was
already broken in my opinion, so I came to the conclusion you can't break
what's already broken.
Good luck.
Michele Sayer

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