After hours and hours and days and days of testing and re configuring ive managed to stop 90% of my performance issues.
First i tested Win 7 64. Average 25 to max 75 fps
Vista 64 service pack 2 Average 30 to max 75 fps
XP 32 service pack 3 Average 60 to max 311 fps
I was unable force of vsync with win 7 and vista using ATT. But under XP i can disable vsync with CCC without any problems.
XP by far offered me the best performance.
I was experiencing random CTD's and bad performance intil i installed sp3.
My specs;
AMD X4 940, 3.6GHz OC,
GA MA790FX UD5P,
4Gb DDR2 800,
HIS HD 4870 X2 with 8.9 cats,
OS: XP 32 SP3
My settings;
Everything set to very high.
Post processing disabled - causes to much blur for my liking.
Disabled AA. Doesnt seem to add much visually but steals huge fps.
Both resolutions set to 1280, 1024.
On these settings i get an average 50 - 80 fps and up to 311 if i look at the sky.
I think its linked to OS. Especially 64 bit OS.
Install the latest service pack and try running the Direct X.exe in the arma 2 game directory.
I had all the probs listed but now im running smooth as.