Ive been testing all kinds of stuff lately, I finally got around doing a head on comparison with an nVidia and ATI card on the same rig.
Mind you Im comparing my 5 year old budget nvidia card (7900GS 256 Mb) with my new last years highend Ati Radeon 4870 512 Mb I bought to replace it.
Its not a fair fight; the ATI card is roughly 3x faster in raw performance and on most synthetic benchmarks (eg http://www.videocardbenchmark....?cpu=Radeon+HD+4870).
So what would happen in IL2?
I ran both cards at medium res (1440x900 2xAA) using fairly common settings (perfect, water=0, ultrapack). I used the "1945" track (from 10s).
The difference between both cards on the "1945" track is.. 25%
http://img190.imageshack.us/img190/1...ersuckage1.png
>> In favor of the (much slower) nVidia card <<<
I couldnt believe that either. I ran both test twice again and got the same result.
It can only be a driver issue so I ran both tests again this time at 640x480 with low graphic settings to completely eliminate the videocard itself as a bottleneck; the difference goes up to almost 30%:
http://img651.imageshack.us/img651/6...ersuckage2.png
Thats how bad ATI's opengl drivers are.
Tested with latest ATI and nVidia drivers.
I checked the IL2 binary with intel's vtune and I dont understand it all, but it does seem to spend half its time in the atioglxx dll so it could be correct.

