Another forum user is using a 660 with his Q6600 but I was showing him examples of his GPU being held back. He does get decent frames in BF4, but nothing to really feel great about. That is why he has the OC thread a few subforums down.
Try overclocking your GPU, that will help a little, there are plenty of guides online, and while your at it overclock your cpu, you will prob get a decent frame boost