I have mine overclocked to 4ghz with just a multiplier increase, this making it a 8350. I haven't noticed any issues with it. Rips through my 3d fractal rendering pretty fast and I'm happy with it.
for BF3, on ultra with a 7870 video card, I get about 50% with my GPU maxxed at 100% usage and my cpu about 60% maxed, so lots of headroom there before the game would be maxed out.
Paired with 16GB of 1866 ram and an SSD for a boot drive, it's pretty damn quick.