Are Open-Source GPU Drivers Sufficient For 4K Linux Gaming?
Last week I published the results of a 15-way AMD/NVIDIA GPU comparison for 4K Linux gaming that was centered around the proprietary AMD/NVIDIA graphics drivers. However, if you stick to using open-source Mesa/Gallium3D drivers and are a Linux gamer, here are some benchmark results comparing the open to closed-source driver performance at 3840 x 2160.
Unfortunately the 4K open-source driver comparison didn't work out as well as the closed-source driver comparison... As shown this weekend, the new AMDGPU open-source driver is rather slow until re-clocking/DPM is implemented for TONGA, so the Radeon R9 285 had to be left out for the open-source comparison. Of my modern AMD GCN GPUs available for testing that then left the HD 7950, R9 290, and R7 370 -- all three of these graphics cards mode-set fine for my 4K display and drove the Seiki HDMI display without any issues.
When it came to testing the NVIDIA GPUs used in last week's 4K Linux comparison, the GeForce 900 series had to be left out since there isn't yet Nouveau hardware acceleration for these new Maxwell GPUs. However, for the Kepler GPUs tested, those 4K Nouveau testing ideas were quickly dropped... I couldn't get any of the GeForce GTX 600/700 series graphics cards to properly set their mode for the Seiki 4K display. The Nouveau driver would only mode-set to 1920 x 1080 on this panel, while the 4K display worked fine on the same hardware when using the proprietary driver -- and both the open and closed-source AMD Linux drivers. Thus all of the NVIDIA GPUs were tossed out of this comparison. The Nouveau driver would have likely run into issues anyhow with the poor re-clocking for Nouveau in delivering low-performance as it is for 1080p, etc, and the crippled video memory bandwidth would be an issue especially for 4K.
So for this 4K open-source Linux GPU driver comparison, only the Radeon HD 7950, R9 290, and R7 370 could be successfully tested. The test selection also had to be limited compared to the results shown last week, with the Metro Last Light / 2033 Redux and BioShock Infinite games not working on the current Mesa/Gallium3D drivers -- at least that should change soon with the current rate of OpenGL 4.x enablement in Mesa.
For the benchmarks that could be completed, the results are on the following pages with the comparison via the open-source Phoronix Test Suite benchmarking software.