This PC will suit you very well.
http://pcpartpicker.com/p/1RzLQ
Its CPU is not that great for overclocking as you're unlikely to get it to run above 3.8GHZ, but it's basicly a Core i7 without the IGP, so that's a pretty good deal.
The motherboard is pretty much the cheapest one that has a SATA 6 port and a front USB 3. There's nothing more to look for in this price range really.
The graphics card is very fast,silent and cool running. Its overclocking potential is amazing.
It ships with a core clock of 925mhz, but I haven't seen a tahiti card that peaks at less than 1100mhz.
The case is very basic. It has everything you need and nothing you don't. Its cooling performance is also very, very good.
All in all it's a very good build.