Graphical screen dying on new FC4 install

[Dotan Cohen]

I just replaced Win98 with Fedora Core 4 on a friends' computer: AMD
550, 128MB RAM. Now, he can work for a limited amount of time (between
20-150 minutes), then the computer gets stuck. Not even the mouse
works. He can, however, switch to a console with CTR-ALT-F1.

When restarted, there is no graphical mode, only console. If he lets
the computer sit for a few hours, he can boot up a graphical screen,
but after some time the problem reoccurs. Nothing in the computer
(open case) seems unusually hot, which was my first thought.

Any ideas on where to look? Thank you.

Dotan Cohen
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