How will my PC run Battlefield 3?

Here's my pc specs.

I have a A8-3870k crossfired with ASUS 6670 DDR5 1GB. This combo works out to be almost as good as the 6770. So basically, lets say I have a 6770. Also, crossfire will only have effect in DX10 and DX11 games so BF3 needs to be ran in dx10 or 11.

My CPU is A8-3870k, 3.0Ghz

8GB Kingston HyperX Ram 1600Mhz

400W Antec PSU(don't know if psus affect preformance or not but I'll just post it)

750GB Seagate

Hyper 212 CPU cooler

Motherboard: ASUS F1A55-M LE - FM1

Monitor resolution is 1650x1050

I just saw the 10$ Battlefield deal but I'm not sure if my pc would be good for it. All I want is preformance that is at least better than consoles, if anything less, I don't really want to play it on pc. How will my pc preform on Battlefield 3 and at what details.

Since not many people have the A8 with 6670 crossfire, I just looked up some 6770 benchmarks and some are just insanely good that I don't even know if my pc is actually gonna be that good. Some more info is that my pc can run Dirt 3 on High, 1650x1050 with 42fps average and on max at 36fps average.

For example, this video

http://www.youtube.com/watch?v=3nTCyP99ni0

Can I trust these videos? Can my pc really run BF3 at max???