GPU Usage problem causing performance issue

[XFreeRollerX]

I'm on the verge of tossing this computer out of the window right now.. this problem has been making me really mad

I'll be playing any game, BF:BC2, CS:S, old and new games.. running along at 100-200 FPS then out of no where my GPU usage goes from upper 90's to 20-40%.. Sometimes i still get decent framerates like 40-60 FPS but everything is just laggy as hell, mouse lag, i kill someone it lags, the screen is choppy like I'm getting 5 FPS

I tab out to check CPU usage and its fine, 40% tops

Get back in game, still 40 FPS, and less than 50% GPU usage


This all started happening recently.. not sure if a driver change or what caused it but I rolled back to 260.99, installed the new 266's that came out couple days ago and I cant get rid of this problem!!!!! Someone PLEASE help me