You haven't noted your resolution that you're running at. I presume its 1366x768 as your sig states a 19" screen. To give you an idea, my rig has a HD5670 and Athlon II X2 250 and from memory I can max out BFBC2 without AA at 1366x768 on about 35-50FPS.
Your CPU is stronger than mine, but your GPU isn't. You'd probably see about 20FPS on max settings 1366x768 as BC2 is very heavy on GPU as long as you have a decent dual core. Lower it to medium settings, you should get 30-35FPS. I can't say for sure as I don't play BC2 anymore and have it uninstalled.
But if you're running on any higher resolution, then you'll get even lower FPS.