I recently replaced my old card, the nvidia 9600 gt with a HD 5770. Im getting lower FPS on the new card then on the old card. How do I fix this? I have 4 gb DDR2 RAM. Athlon x2 6000+ 3.0 Ghz. Im not sure about the power supply though and I don't want to over clock anything. The FPS seemed higher with the 9600 gt than the HD 5770 in bad company 2.