Well I am an AMD fan... You can get a 6core for 199 3.2 ghz that easily overclocks to 4.1
Memory... i would upgrade to DDR3 1600 ... Its not expensive at all.
The motherboard you are wanting to buy is over kill imo for that processor ....
The Video card is nice, but since we have no clue WHAT it will take to run BF3 yet I would wait on it. You can bet your ass many card makers will have a card out with BF3 included for free

I am currently building a 6core 12 GB system with a 560 card for under 800 dollars. I will post an article about it soon.