gtx 280 acting really retarded?

[yashara]

i was playing cod WaW on my gtx 280x2 and i can usually max out all settings with 4xAA on 1920x1200, but for some reason im only getting 30 fps exactly, doesn't go up or down, i tried benchmarking it,

Min Fps: 30.00
Max Fps: 30.00
Average Fps: 30.00

what do i do?