wierd, my xp home, can run two copies of prime95 dont have any smp software, so cant really test that. both cores work, and work well at that. and dual core, goes far beyond, useless, its extremly useful, when multi-tasking. ex. run a game, and a game server, from one machines, no lags, no FPS hit, etc. still not sure, if that actually means, dual core, rather dual processor. or else, quad core wouldn't work in xp pro, and you'd have to goto 2k3. also same goes for intel HT processors too then, they only work under xp pro? and are completly usesless in xp home? i just used, CliBench Mk III SMP version from what I can see, SMP works in XP Home, anyway to prove it dont?