AMD Radeon RX 480 On Linux
First up are some Dota 2 OpenGL benchmarks (the Vulkan results are later in this article). Note that with these results, the AMD results with the "- PRO" postfix are when tested using the AMDGPU-PRO 16.30.3 driver while the Radeon cards without any mention of PRO were tested on the Linux 4.7 + Mesa 12.1-dev open-source driver stack.
With the Dota 2 OpenGL results, we see the Radeon RX 480 is coming up short of the Radeon R9 Fury but still well ahead of the Radeon R9 290. In relation to NVIDIA, Dota 2 on the RX 480 was running between the GTX 960 and GTX 970. Exciting to note is the close performance of the open-source Polaris driver code relative to the AMDGPU-PRO binary hybrid driver.
With the Unigine Heaven tests is where AMD has traditionally been able to compete well with NVIDIA on Linux and here it shows the RX 480 in much better capacity. When running Unigine Heaven, the Radeon RX 480 performance was between the GTX 980 and GTX 980 Ti. The AMDGPU-PRO and RadeonSI Gallium3D driver performance of this Polaris graphics card was quite close. Here it's fun to see the AMD performance scaling over the past GCN generations.
Unigine Valley, similar to Heaven, showed there's nice potential out of the Radeon RX 480 with either Linux driver stack when the game/engine plays nicely with the AMD Linux driver code. The RX 480 with both Linux drivers still came up just short of the GTX 980 Ti.