Why AMD? Get an Intel E8200 or E4500 (depending on budget) and overclock the crap out of it.
Anyone who recommends a GTX for anything below 1600x1200 resolution gaming is barking up the wrong tree.
8800GT is pretty much the only viable option for a gaming card at the moment. Other than that, you could get an 8800GTS 512mb, which has even more...
Does not matter how many PCI-E slots a motherboard has, unless it has SLi support (which only nVidia chipsets do) then it cannot run SLi....
No, it is not.
You can't have 4 cards in SLi. Max available is 3 on a 780i board, or 2 dual-cards ( as in, 2 chips on the same PCB)
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