I dont know what it could be...I got terrible FPS on Black ops (35-40) and its choppy as hell. My own build. Tried 2 different cards with same exact lag. My CPU? How do i show you my screenshot of the GPU Z?
Windows 7 Enterprise
AMD Phenom II 940 3.0 Ghz Quad core
ATI HD Radeon 5770
2 X 2g G.Skill Dual Channel DDR2 401.8 MHz (1:2) @ 5-5-5-15
320 GB Western Digital
Other card was the Nvidia GTX 460, and i got the same lag on the lowest resolution and the highest resolution...it dont make a diff. Thats wuts making me think its the processor....because I tried a new card and I also have a new motherboard.