I agree with welshmousepk.Even though you said that you're not interested in the i5 I think that it's a mistake to overlook it as it's a great performing CPU.
You said that your budget was $1,200.
I think that a good highly potent system would revolve around 2 Radeon 5850 cards in cross fire (about $520 U.S.) and either a P55 i5 (cheaper) or P55 i7 860 (better) CPU.Here is a recent review of 2 5850 cards in crossfire.http://www.tomshardware.com/reviews/radeon-hd-5850,2433.html
I prefer the 5850 over the 5870 though because of its lesser price (bang per buck).
If you can swing a i7 920 and a inexpensive X58 motherboard go for it but don't overlook the P55 i7 or i5