In every game I try to play, the game always runs smoothly for about two seconds and then the fps tanks to about 5, but then it goes back to normal and stutters the whole time. The only game where this didnt happen is Battlefield 3. I have tried the driver solutions, but I cant figure out the problem.
These are my specs:
CPU: Phenom x4 965
GPU: Asus HD 6870
RAM: 8 gigs
Display: Sony HD TV
It sounds to me like your 6870 is stuck at 2D clocks.
There are three different steppings for a card:
Idle (I think that's 100/150 for the 6870), 2D (Web browsing, videos) which are around 400/500, and 3D which is the full clock speed.
My old 6870 would always stick at the 400/500 clocks, which was really annoying. It's a driver problem, and has to do with Power play.
If it isn't too much trouble, can you download an application called GPU-Z, install it, and then tell me what the clock speeds are when you run a game? That would help see if this really is the problem.