BF3 Lag Issue (6850 Crossfire)

[Chaos Water]

I'm having major issues when playing BF3 on my computer, I have 2 6850's running in Crossfire, the first being a Sapphire HD 6850 1GB and the second being an XFX HD 6850 1GB.

Everything on the game is set to maximum and my computer should easily play the game on an Acer 23" 1920x1080 HD Monitor.

My CPU is the AMD FX 8150 3.60GHz
PSU is the Coolermaster GX650W
RAM - Kingston HyperX Blu 4 X 2GB 1600MHz

I don't understand why I'm having this issue, I've searched around and I've heard that lag spikes are caused by cards in crossfire but I'm not sure whether to believe that.

Could someone please suggest a way on how to fix/improve this issue.

 

[Viking2121]

MAX settings! That might be the problem. I run 2 HD5850's and both cards are 1GB cards, And no the Vram does not add to 2GB. But when I run BF3 maxed out, it lags, You will need to turn off AA and motion blur because this game will use more then 1GB of vram, After I did that the games runs perfect at 1080p. Also Running at high with 2x AA and the game runs good, but the 2x AA is still like 0x AA at distance.

As I said, the two 1GB cards do not add up to 2GB of vram.


Edit: Close out any monitoring program when playing BF3 and the browser, that can cause it, Also I use the Widows Gadgets, that effects my fps just a little anyway.

 

[Chaos Water]

Thanks for the help, it has made a slight improvement but even when I run the game on High Settings I still get lag and that stupid micro stuttering.

Will AMD ever bring out drivers to eliminate this issue!