Not all Unhappy campers on ati

[bridgman]

Upgrade to r300g built with llvm support if you are not using that yet. It will significantly improve your 3D performance.

Yep. Business_kid, the rs6xx hardware does not have vertex shaders, so geometry processing is done on the CPU. The proprietary drivers use a JIT compiler to generate efficient CPU code for the shaders, while the open source drivers used a slower solution.

If you go with the Gallium3D driver (r300g) built with llvm as agd5f suggested then llvm is used to JIT-compile the shaders in a similar what to what the proprietary drivers do, giving you much higher performance on the geometry portion of the workload.

[whizse]

[...]
Also more games work - waiting for trine to work with ati/intel.

Ho hum, it was an Intel employee who added the necessary changes to support Trine. In other words, it was working on Intel before anything else...

[Kano]

I define working a bit differnet than you... It starts but the rendering is wrong.

[whizse]

I define working a bit differnet than you... It starts but the rendering is wrong.

Before anholt added ARB_draw_buffers and ATI_draw_buffers it wasn't working at all.

[Kano]

Correct, but do you see correct rendering with amd+intel mesa? Nouveau with dx9 card is also wrong and seems to work with .38 kernel only, but dx10+ is fine.

[pingufunkybeat]

nouveau was the only Mesa driver to render Trine correctly, but it was actually a case of two bugs cancelling each other out.

[Kano]

How do you explain the speed difference? Press f8, then /show_fps 1

[pingufunkybeat]

It's hard to compare because there are many parameters.

With Very High quality @ 1280x800 using HD4550, I get 6fps on average.

Keep in mind that this was the cheapest modern card two years ago, and is the second lowest level r700 chip on the market. I got it because it was the cheapest, just to bridge the time until the OSS drivers became usable.

I'm considering buying a new one, a passively cooled HD6xxx or similar, now that the drivers are maturing.

[pingufunkybeat]

If I remember correctly, nouveau actually has a really sick throughput rate, much higher than most OSS drivers and close to the blobs. That's why it shines in some benchmarks while (for example) r600 drivers are CPU-bound.

I'm expecting Hyper-Z, texture tiling and some other optimisations to improve r600 performance, but after that, it will probably be time for slow, gruelling optimisations.

[Kano]

I have got the same card in my ati pci collection (x1600,hd4550,hd5670). The thing is the speed differences between ati oss and fglrx drivers are really extreme. Up to factor 10 with trine, when you look at nvidia the difference is maybe factor 2, sometimes even less compared to nouveau. I did not test nouveaus speed before, but i think it is really impressive what could be archived with those drivers even without docs. Here in the board many ppl think they support oss drivers when they buy ati cards. That's definitely the wrong investment if you want fast oss drivers...