What size monitor will you be using? Anything under 1900x1200 is practically useless for that card.
No offense, but that's not a very well thought out build. I suggest you go with an i7 and a dual GPU setup since the 5870's are hard to obtain. But all in all, it really depends on your monitor.
Case: Silverstone Raven
http://www.newegg.com/Product/Product.aspx?Item=N82E16811163135
HDD: Samsung F1 (For storage)
http://www.newegg.com/Product/Product.aspx?Item=N82E16822152100
PSU: Xigmatek 750 watt modular PSU
http://www.newegg.com/Product/Product.aspx?Item=N82E16817815002
RAM: G. Skill RAM DDR3 1600
http://www.newegg.com/Product/Product.aspx?Item=N82E16820231193
Motherboard: MSI P55
http://www.newegg.com/Product/Product.aspx?Item=N82E16813130239
CPU: Intel Core i5 750
http://www.newegg.com/Product/Product.aspx?Item=N82E16819115215
Optical Drive: Lite On BluRay Combo
http://www.newegg.com/Product/Product.aspx?Item=N82E16827106292
This is completely optional, but you might enjoy it. It's to install your OS on. It will cut down boot time to seconds. Just something cool to have on your side, especially in bragging situations.
http://www.newegg.com/Product/Product.aspx?Item=N82E16820141419
I haven't chose a GPU yet because of the monitor situation. This build should be a little cheaper and I haven't use any combos yet and that should cut off another $100+ easily.