If you're going to buy right now, for $1500:
http://www.techreport.com/articles.x/17102/6
But with two 4890s rather than the suggested one. This'll play any game except Crysis on max settings (but nothing plays Crysis on max). Two 4890s is the fastest graphics setup that's at all justifiable; going to four GPUs gives 10-20% more at twice the cost and power consumption.
But, wait until mid-September for the next generation of DirectX11 cards, and Lynnfield to make Core i7 more affordable. Or for AMD to release the X4 965. You'll get much better value for the same amount of money. You need a DX11 card to get the most out of Windows 7 and some upcoming games.
It pains me to not recommend an AMD processor, but there are none in your price range at present.
