well... i have 1 8800GTS and i was ganna buy another one and a new PSU so i could SLI them. but the it hit me... will my 939 X2 4400+ bottleneck the 8800GTS's in SLI?
at those resolutions you'll see a gain in performance since it is a fairly high resolution, but keep in mind, not all games like sli. what kind of games do you play?