https://bugs.freedesktop.org/show_bug.cgi?id=91880
--- Comment #99 from Brian brian@egee.io --- Just wanted to throw my chip on the pile..
I'm running an R7 360 (BONAIRE, uses GCN 1.1, just like HAWAII)and I'm having the exact same issues. And forcing DPM to performance mode fixes the issue for me.
Using kernel 4.6rc5 on openSUSE Tumbleweed.