AMD's Windows Catalyst Driver Remains Largely Faster Than Linux Drivers
With last week having delivered our latest Linux vs. Windows NVIDIA benchmarks where we found that the NVIDIA Linux driver can outperform the Windows 8.1 driver with OpenGL workloads, the tables have turned to looking at the AMD Windows vs. Linux performance using the latest code. In this Ubuntu 14.10 vs. Windows 8.1 comparison, the open-source Radeon driver on Linux is also being tested against the Catalyst drivers.
This AMD cross-OS comparison is looking at the performance of Microsoft Windows 8.1 Pro x64 with all available package updates and using AMD's Catalyst 14.9 driver package compared to Ubuntu 14.10 x86_64. Ubuntu 14.10 was tested with the fglrx-updates latest stable driver (fglrx 14.20.7 / OpenGL 4.4.12968) and then also when using the latest open-source graphics driver code: the Linux 3.17.0 kernel plus Mesa 10.4-devel from the Oibaf PPA.
The tested graphics cards for this comparison were the AMD Radeon R9 270X, R9 285, and R9 290 graphics cards. While the AMD Radeon R9 285 is the newest graphics card and very interesting as being the first GCN 1.2 GPU, unfortunately on the Linux side it's less interesting for this comparison.
The R9 285 wasn't supported by the fglrx-updates driver and the only driver package of Catalyst supporting the R9 285 is its special-released fglrx 14.30 series driver update, which unfortunately doesn't work on Ubuntu 14.10 due to xorg-server compatibility or hitting some other issue. At the time of testing and writing there's been no newer release of the R9 285 Catalyst Linux driver since its launch-day driver release. On the open-source side, the R9 285 is currently unsupported. The R9 285 isn't being supported by the current open-source driver code but is the first ASIC to be handled by AMD's new unified AMDGPU driver stack that's yet to be publicly released. It doesn't look like the new driver will be mainline in the necessary repositories until very late 2014 or early 2015 so for now the Linux support is a bit sad for the R9 285 compared to AMD's overall friendly open-source driver support.
The Radeon R9 290 Hawaii GPU series is at least running fine on the open-source Linux driver stack using the very newest code. The Radeon R9 270X has long ran fine with the open-source Linux driver code.
That's the summary of the test configuration for our AMD Radeon Windows 8.1 Pro vs. Ubuntu 14.10 testing. On the following pages are the benchmark results via the Phoronix Test Suite for this latest graphics comparison.