So, if you have the dollars where do you put your money? – Well, surprisingly the best setup here is the three-GPU configuration that a Tri-SLI GTX 285 card offers. For the most part the HD 4870 X2 manages to suck the most power while offering the worst performance in today's most intensive games (with only a few exceptions being seen).
I suppose the real question is why would you buy Quad SLI over Tri-SLI? - For starters, a single GTX 295 is faster than a GTX 285, so in the event that you want to start with baby steps and take the SLI / Tri-SLI / Quad SLI leaps later down the track, you're going to get better performance today.
As weird as it sounds, the four-GPU setup that utilizes two GTX 295s is actually also cheaper than purchasing a three GPU configuration that uses three GTX 285s. The cheapest GTX 295 on offer over at Newegg is a BFG Tech card and comes in at 499.99 USD, whilst a BFG Tech GTX 285 will cost you 379.99. The Quad SLI setup also manages to use less power and it also doesn't run as hot. There’s no denying the Quad SLI setup is awesome, but the Tri-SLI GTX 285 one is really the fastest VGA setup to date.