Tonga AMDGPU Performance On Ubuntu 16.04 Has 80~90%+ Performance Of Catalyst

Earlier this week was the How Ubuntu 16.04 Is Performing With AMDGPU/Radeon Graphics Compared To Ubuntu 14.04 With FGLRX, which showed off some interesting open-source Radeon Linux driver results but the Radeon R9 285 "Tonga" graphics card at the time couldn't be tested on Ubuntu 16.04's kernel due to a regression. That issue is fortunately now resolved in the latest Xenial Xerus kernel so here are those numbers.