Laging DX9 Games

So since k can't get any help in the game section... hi so im on my second GPU, and my graphics for all my DX9 games (which is pretty much all of them) are all lagging. this the the second GPU that ive tried. first i tried with an ATI 6670 and now im trying with ATI 6770. i doubled the power of the GPU and they still lag. now on my internal GPU, they dont lag at all on good graphic settings, but no matter how much i change the graphic settings on the 6770, nothing helps. my current external GPU is DX11, and my internal GPU is DX10.1 also BFBC2 and DiRT 3 do not lag at all on 1080 with high to max settings and i get a good/ even frame rate on the 6770 and they are DX11 games. on all the DX9 games, its very uneven and averaging around 15-20 occasional 40fps and occasional 10fps. i have all the "best performance" settings checked in CCC, and have it set to 16bit color. also the drivers are all up to date, updating/ installing DX9 does not help. like i said, no matter if its on 1080 or 800 resolution, it lags all the same.

any ideas? i would love to have this system up and running 100%

I've played with the drivers and drivers don't seem to help with anything.

Any ideas?

Thanks.

any ideas at all?

any help?