Radeon R9 290 Testing Update With Linux 4.10, AMDGPU-PRO 16.50

With the post Christmas ad rate slowdown I finally found the time to run some fresh tests on my Radeon R9 290 that since around Linux 4.7 has been performing abnormally slow but has been working fine with AMDGPU-PRO. I carried out some tests with Linux 4.10 and also ensured linux-firmware.git was the latest, but still it's somewhat of a mystery...