Severe performance issues with ATI graphics cards

Questions & Answers
1

I noticed that Unity runs terribly bad on ATI graphics cards, both in the editor and in standalone builds.
Loading and building the same project on 4 different machines, two of them running with ATI cards resulted in huge performance drops compared to the other two running nVidia cards.

I’m talking 10 times worse here, with the profiler showing on one machine (with ATI) that the GPU takes 26ms to render the scene, while another machine running (a weaker) nVidia shows that the GPU takes 2ms to render the same exact scene under the same exact conditions.

The scene, by the way, consists of 10 low-poly meshes and one directional light with hard shadows. The 10 models consist of 26K triangles together, using the default diffuse shader. No physics was used.

Again, all tests were performed under the exact same conditions regarding resolution, cameras, scene etc.

It seems that Unity favors nVidia graphics cards greatly over ATI .

Has anyone else met with this issue, or is aware of this condition? As mentioned these results were consistent on 4 different machines, all of which rather powerful, using the newest hardware.

It’d be very helpful if anyone can confirm this issue or report fixes if there are any as I’m in urgent need of a solution.

Thanks in advance for all your efforts.

2

Well, apparently it’s an issue with the profiler itself.

A rather misleading one, at that. When the profiler is open the performance drops significantly however when the profiler is closed Unity performs as expected.

This issue is only present when using ATI graphics cards, and there is no issue with nVidia cards.

I suppose the problem is solved, however it does mean that developers using ATI cards cannot count on the profiler at all.

If someone can prove me wrong I’d be more than happy.