If you go with x58 chipset you will be stuck with the i7 920 unless you are willing to pay over 500 for a cpu upgrade.
The 4870x2 runs very hot and you really need it on at least 40-50% while gaming - its quite noisy at that range but still bearable.
http://www.ebuyer.com/product/131950 - Still have a few in stock at e-buyer. I would grab them soon.
Don't forget the RAM!
2x 260 is the best value. But since you got such a 'substantial' amount of money, I'm sure price doesn't come into play. In which case go 285 x2
I agree with Loom - save your money for a rainy day. If you don't get a job soon you could go into debt and we already have enough of that as a...
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