5870 is performing much worse than it did a few months ago

[sebc2s]

Hi, I have an i7 920, 6GB DDR3 RAM, ASUS PT6 SE and a Sapphire 5870 GPU. When I first starting using the card for games such as Starcraft 2, Battlefield Bad Company, and Call of Duty: Black Ops, my FPS was amazing, I never noticed any stutter whatsoever. Now it seems that I am forced to bring the graphic settings on these games down to medium to get the same playable FPS that I was getting before.

I have defragged my computer, cleaned up unnecessary files and I have the newest drivers for my GPU(11.5) Anyone know what the problem could be?

 

[Chainzsaw]

Have you installed anything else besides the newest GPU drivers?

Also try installing Game booster. See if that helps. If it does - try to look for what programs it disabled.

Also one more thing...have you changed your AA settings in your control panel (for example setting it to X8)? Normally those override settings inside your game.

Have you changed your resolution? If you increased your resolution, that will affect gaming performance as well.