SMP machine hangs ofter

[Lapo Luchini <lapo@lapo.it>]

I've got a SMP machine (dual P2-266) and happily installed Debian over
it ('testing' release, but with 'stable' I had the same problem): it
hangs very often when using X windows.
It 'hangs' the hard way: stopped mouse, keyboard not responding.

It's a known issue or it's just me?

Someone can give me some good advice? Or some mean to test the machine
just in case it is a phisical fault randomly exploited only by X?

Thanks ^_^

--
Lapo 'Raist' Luchini
lapo@lapo.it (PGP & X.509 keys available)
http://www.lapo.it (ICQ UIN: 529796)