Advice building brother a new computer

[Epoch]

Hey everyone, over the last few days I've been looking over parts for a computer I'm going to build my younger brother for a christmas present. So far I've gotten the following:

Cpu: http://www.newegg.com/Product/Produc...-808-_-Product
Case: http://www.newegg.com/Product/Produc...82E16811119245

However, I'm unsure what to go with as far as motherboard, ram, video card, and power supply; though I was looking at these:

Ram:http://www.newegg.com/Product/Produc...82E16820231428
Video Card: http://www.newegg.com/Product/Produc...82E16814130826

I've read ati is best paired with amd, should I go that route? Games run fine except for wow (he has low fps in 10 mans and just locks up in 25s) and bf3 (lags nonstop for him), my thoughts were the cpu and video card are holding him back. He's running a dual core athlon x2, win 7 64, with 4 gigs of ram and a gtx 460 video card.

He plays similar games to me: wow, starcraft 2, skyrim, battlefield 3 and swtor. Would only be going with 1 video card, so don't need sli.

Budget - $500 to $600
Resolution - 1900x1080p
Games / Settings Desired - Wow, swtor, bf3, bf4 if possible. Settings on Good.
Any other intensive software or special things you do (Frequent video encoding, 3D modeling, etc) - Nope
Country - USA
Do you need an OS? Have Win 7 64 bit.
Do you need peripherals (e.g. monitor, mouse, keyboard, speakers, etc)? Nope.
Parts that can be reused - Cm tower and 955 black edition cpu.

Any thoughts / advice is greatly appreciated. Thanks for your time.