Quote from: lbr on December 13, 2016, 10:14:13 AM

Also, any interferance with the GPU except the miner can cause GPU to go idle/low power state.
F.e. - Screen saver/GPU-Z/MSI Afterburner/any soft which uses GPU.
Some software on launch/some rendering/profile apply/etc makes GPU to enter 3D mode, after it is finished GPU goes idle/low state.

Or it simply hangs in OpenCL due to unstable clocks and then resets itself.
Visually it can be seen on display as very quick flicker.

I just installed windows 10 to see if that could solve the problem. Same Bios settings (8x 4x 4x, gen 2 PCIE ports, inboard audio disabled), amd drivers ver 16.9, afterburner, CDM ver 7.4, aand thats it.

Afterburner mods: +6% vcore, +10% power limit.

Results: 1 gpu mining at 4mh/s, 5 gpus mining at 25 mh/s. And a new problem: I dont see any speed improvement by modifying the clocks, its like afterburner didnt work. I havent overlocked my gpus since the release of ZCash but I remember getting speeds of up to 29 mh/s per gpu with my other rigs.