Advice on i7-920 gaming build

[vercingetorix_64]

i was wondering if someone might give me advice on my build.
the computer will be used for gaming and as a studio.

the only parts i must have are i7-920, Obsidian and 5970 or 5870.
i only require the listed parts.

EVGA X58 SLI LE

Corsair Dominator DHX+ DDR3 1600MHz 6GB CL8, for core i7

Corsair H50

Corsair HX 1000W

Corsair Obsidian 800D

Intel Core™ i7 Quad Processor i7-920

Samsung SpinPoint F3 1TB

XFX Radeon HD 5970 2GB GDDR5 (thinking about 5870 to lower the price)

Microsoft Windows 7 Home Premium EN OEM, 64bit

 

[vercingetorix_64]

couldnt edit, so i'll just add this..

i know nothing about overclocking and will probably not attempt it.
i will build the computer myself, but that too is something i have little experience with.