i multibox and my laptop can run 4 very smoothly (not at highest settings tho, ofcourse. But at acceptable settings.) but I've ran as much as 6 without noticable problems at the time.

Qosmio x300
X9100, 4gb ddr3 1066, en9800m gtx. (And soon getting a SSD disk for it too! Might increase performance considerably as well. )


I have a desktop that's better for boxing, since this is a dual core and my desktop a quad. But quite frankly, I love the mobility too much. Whenever I do PvE/PvP intensive stuff that I need a multiscreen set up for, I use my desktop. But I'd say I use my laptop 90% of the time. Even tho the desktop is 'right there'. :P