Hello , I need help about getting graphic card for my PC .
I need graphic card for gaming . Graphic card which I have now is not so good to i can play games like BF3 .
I ' m running MW3 , medium graphic on 30 FPS .
I wouldn't. A 1.8ghz dual core processor would be lucky to handle an HD 6750, let alone a 6850. As you said, there's a SIGNIFIANT bottleneck, to where you're only getting about $70 of performance out of that $130 card.
The best suggestion I have is to save up money for a much larger upgrade of basically everything - if you were to buy any modern card more powerful than the 6790, I'm going to guess that you'd need a new power supply to go with it. If you were to buy even an HD 6990 and stick it in your current system, you'd still get absolutely horrible framerates in BF3, because your CPU just wouldn't be able to keep up with it.
Save up your money if you want to get a decent gaming rig. If you absolutely must have something NOW, then I'd go for this, but don't expect it to perform all that well in BF3. IF you do buy that, it would be basically worthless when the time comes for an entire system overhaul, and you'd be out $80. Once again, the best thing you can do is save up your money.
ati 5570/6570. Anything more and you wont notice the difference due to cpu bottleneck. Even then CODMW3 will run like crap due to the slowness of your CPU. I dont think it even meets the minimum specs for BF3.