I have the following problem which I think is hardware related because my first step to replace W98 with XP, did not help. It could be IE related, though.
While surfing, I occasionally get into a state where the OS hangs completely. No kbc, no mouse, I have to press the reset button.
Sometimes it happens, sometimes not. Usually it occurs in the same sites, that got me suspicious of heavy Flash animations. E.g. , many times it happens in Yahoo Web mail, right after loading the page that comes up after sending an email.
It was recommended to me to upgrade my graphics card. I did that, from Voodoo3 3dfx 16 Meg, to nVidia Geforce 4 64 Meg. That did not help either.
All my fans work.