Yeah, the GTX590'a are dul GPU cards. I'd say go with two 7970's or two GTX580's. Hardly any games take advantage of quad-anything (SLi or Cross-Fire) yet and the GTX590's are power hungry suckers that don't overclock very well unless you flash the BIOS and even when you do you don't get much more out of them. 7970's OTOH OC like crazy, are new tech, and don't pull as much juice, so they run cooler. Also, you could wait for nVidia to release Keplar (spelling?) which is rumored to smash AMD's 7970 offering.
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