Ram will do it....[random crashes].
As for 'breaking XP'....it's made up of a Kernel and a Shell...and last I heard if you had both of those you had a 'nut' and they can certainly be broken [cracked]...
Hus....no-one can ever be totally sure about anything when it comes to computers....there's just too many variables.
A faulty ram 'address' being accessed can cause odd crashes...as can a system component overheating.
With ram...if there is more than one stick...try removing one or swapping positions...see if the behaviour changes.
In the bad old days it was common to come across faulty ram...and/or faulty mobo banks, but it seems less common these days.
My most recent BSOD [in XP] was initiated when accessing/updating a fairly large database...and my 'theory' was that 256meg wasn't enough to cope....and If I'd stuck in another stick it might solve it....but so much of this 'odd' problem solving is down to trial and error....[I haven't got a spare stick to try it....yet]...