xaishi, in my unofficial tests ( <img src="/ubbthreads/images/graemlins/stupid.gif" alt="" />) there was a dramatic difference in going from 512 to a gig and then back again. sadly (sorta <img src="/ubbthreads/images/graemlins/smile.gif" alt="" />), i have 512 sticks so couldn't test 768.
512 (i have matching corsair memory) results in extreme delay in release of memory upon exiting the game. sometimes resulting in a BSOD.
1 gig mostly handled the situation, and resulted in no BSOD.
minimal differences in gameplay however, mostly because there is not wave after wave of enemies appearing on screen at once, say like in diablo II (my guess).
vipe, i can't imagine playing this with 256! woohoo! <img src="/ubbthreads/images/graemlins/biggrin.gif" alt="" />
one can only imagine the fun people must have if they're also running winME! ouch.