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View Full Version : ATI vs nVidia OpenGL driver performance.. stunning result



Duvel123
08-11-2010, 12:14 PM
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) (http://www.videocardbenchmark.net/video_lookup.php?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/img190/1472/atidriversuckage1.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/img651/6853/atidriversuckage2.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.

pupo162
08-11-2010, 12:20 PM
TBH, may the tests be right, but my brand new ATi Card vs my 2 year old nvidea card was like changing from a slide presentation to a 3d movie: no regrets.

Most likely if you kick the graphics in both the cards you will see that at high end perfect graphics the nvidea will melt down and your ATI will keep up blasting.

This test only proves that if you put a ferrary and 4x4 in a dirty road the 4x4 will go faster.... try and put the gamein the highway and you will see...


Still, my above comment does not denie the fact that there is a well know issue with ati open GL... and overrall this was my last ATI card due to all the driver problems..

cheers

Duvel123
08-11-2010, 12:25 PM
Yes if I increase resolution further and up the AA and turn on water=2, the ATI cards becomes faster. no doubt. The ATI card can do 24xAA at pretty much no performance loss, the old nVidia card simply cant cope with that.

The issue here is not such much the 2 models I happened to have at hand; the issue is that it seems the ATI card comes with a 30% driver handicap over any nVidia card in this game (and perhaps other opengl games). That would be true for new highend cards as well.

Now compare prices between any given card and one that is 30% faster... actually, compare prices with one that is 3 TIMES faster given my results.

pupo162
08-11-2010, 01:23 PM
the handicap of ati cards with open GL is a known issue. The graphic of yours dont say nothing new except for showing how worse they are- 30% worst.

the truth is, for a IL2 only player having a last century nvidea card is enough, but there are more games out there.

Xiolablu3
08-11-2010, 03:19 PM
How did you clean the PC from the Nvisia drivers and software before you put in the ATI card?

I remember when I got my first ATI 8500 to replace a geforce 2 MX and the performance was awful UNTIL a reformat.

Maybe I could have used some kind of driver cleaner, but the geforce left behind something that the ATI card didnt like at all.

Ba5tard5word
08-11-2010, 03:49 PM
On my old computer with an 8600GT I was able to max everything out on Il-2 but only if I had the resolution set to 1152 x 768, fps was probably around 60 fps with v-sync on. I dunno how an 8600 compares with a 7900.

On my new computer which has a GTX 260, I can set my resolution to either 1680 x 1050 on my 19 inch monitor or 1920 x 1080 on my 32-inch TV and I get the same high frame rates of about 60 fps with v-sync on.

Duvel123
08-12-2010, 12:29 AM
Originally posted by Xiolablu3:
How did you clean the PC from the Nvisia drivers and software before you put in the ATI card?


I first tested on 2 different windows (7 64 bit) installs; one that always had been on nvidia and a new one that only had seen an ATI driver. When I reran the tests I did both on my new "ati windows" install and it made no difference.

I also ran driver sweeper but that didnt pick up anything suspicious (an empty folder and physx). The conflicting driver "garbage" is something from the past I think. Maybe it was due to XP, maybe the old drivers but there seems to be no issue on w7 with todays drivers. Keep in mind on w7 you can run nvidia and ati drivers alongside if you have 2 different videocards in your PC.

I also had the conf.ini tuned for the ATI card (disabled a lot of nv specific extensions that caused purple haze bug and what not). I didnt change the conf.ini when i ran it on my NV card.


On my old computer with an 8600GT I was able to max everything out on Il-2 but only if I had the resolution set to 1152 x 768, fps was probably around 60 fps with v-sync on. I dunno how an 8600 compares with a 7900.

On my new computer which has a GTX 260, I can set my resolution to either 1680 x 1050 on my 19 inch monitor or 1920 x 1080 on my 32-inch TV and I get the same high frame rates of about 60 fps with v-sync on.

A faster videocard will allow higher resolution (/aa/af/water/..) settings with no or minimal performance loss. Thats true for my ATI card as well; I can run it at 1920x1200 with 8xAA and the performance is almost the same (the old nv card would collapse with those settings).

Here is the thing though; at 640x480 the performance is completely CPU limited. So it seems that the ATI (opengl) drivers put a lot more load on the CPU.

This wouldnt be a great problem if IL2 made use of our idle cores or if CPU performance wasnt a major bottleneck like in many other games, but at almost any setting and with any CPU, CPU performance in IL2 *is* a bottleneck. Increasing the load by 30% due to crappy drivers will therefore result in substantially lower performance. Probably at settings that max out your videocard (say 2560 resolution with 24xAA) the difference between ATI and nVidia will shrink.

Think of it this way; if you buy an ATI videocard, a side effect is a ~30% reduction in CPU speed. (for IL2 obviously)

Bearcat99
08-12-2010, 09:36 AM
Bear in mind also that with some resolutios you don't need as much AA.. When I used a 19" CRT I used to run it at 1024x768.. then on a lark one day I tried it at 1280x960 which is the same ratio but at a highewr resolution.. to my surprise I got better definition and after some experimentation I was able to lower my AA to 2 I think it was.. at the timem I had a Nv6800GTOCd ... and got maybe a 1-4 fps hit.. but it was worth the trade off because at the higher resolution the graphics were everall much better..

Swivet
08-12-2010, 01:12 PM
Originally posted by Xiolablu3:
How did you clean the PC from the Nvisia drivers and software before you put in the ATI card?

I remember when I got my first ATI 8500 to replace a geforce 2 MX and the performance was awful UNTIL a reformat.

Maybe I could have used some kind of driver cleaner, but the geforce left behind something that the ATI card didnt like at all.


I found this link most helpful

http://www.rage3d.com/board/showthread.php?t=33606840

megalopsuche
08-12-2010, 06:42 PM
To the OP, when you say latest drivers, which drivers did you specifically use for nvidia? I'm looking at the latest 258.96 drivers and wondering if it won't ruin Il-2.

bugbuster77
03-29-2011, 07:49 AM
Yes if I increase resolution further and up the AA and turn on water=2, the ATI cards becomes faster. no doubt. The ATI card can do 24xAA at pretty much no performance loss, the old nVidia card simply cant cope with that.

The issue here is not such much the 2 models I happened to have at hand; the issue is that it seems the ATI card comes with a 30% driver handicap over any nVidia card in this game (and perhaps other opengl games). That would be true for new highend cards as well.

Now compare prices between any given card and one that is 30% faster... actually, compare prices with one that is 3 TIMES faster given my results.

I absolutely agree with you. I'm a 3d programmer. I'm working with opengl and I've had the following results:

on a AMD athlon64 dual core, geforce GTS 250 the part of the code related to drivers call is 1.5/2 times faster than the calls on a Intel i7 quad core with a ATI HD 5850.

The ATI card is faster (shaders, fillrate, geometry) but ATI ogl drivers are about 1.5/2 times slower than NVIDIA.

Swivet
03-29-2011, 08:56 AM
Originally posted by Xiolablu3:
How did you clean the PC from the Nvisia drivers and software before you put in the ATI card?

I remember when I got my first ATI 8500 to replace a geforce 2 MX and the performance was awful UNTIL a reformat.

Maybe I could have used some kind of driver cleaner, but the geforce left behind something that the ATI card didnt like at all.


You'd have to go into the registry and delete anything to do with "Nvidia"

http://forums.nvidia.com/index.php?showtopic=16154