Also ... MultiGPU performance is ... temperamental.
I have 1 run at 44FPS average with MultiGPU on on Crazy 1080p with HD7970 6GB + R9 280 3GB + i74770K.
Remaining runs are all at or below 26FPS.
I have tried reinstalling the Drivers and verifying game files.
I managed to fix the poor FPS issue by fixing Windows 10 sfc /scan corruption, uninstalling and reinstalling Ashes, and uninstalling and reinstalling AMD Crimson 16.7.2
I can get consisten 46 FPS in multiGPU now.
I still however see the Lower Right Hand Corner screen corruption.