Zane said:NO. Jesus. The price and power requirements for that are way too huge for such a small performance gain. If he really wants to go the SLI/Crossfire route, then he should get two 6950s, which will absolutely demolish every game out there for like half the price and it will sap much less power to boot. 2x 580s are completely unnecessary and quite frankly, just stupid.
Besides, we should be asking about his resolution. Because if it's less than 1600p, then even one GTX 580 is unnecessary.
oh and seconding the bit about Velociraptors being useless. If you're spending that sort of cash on a HDD, just buy an SSD.
3x 1080p 3D monitors with 8x MSAA. Nuff said.