https://bugs.freedesktop.org/show_bug.cgi?id=93826
--- Comment #61 from Pavel Bordukov pa5hgan@inbox.ru --- (In reply to Alex Deucher from comment #60)
Created attachment 131983 [details] [review] possible fix
It works for me (MG279Q, R9 290x, vanilla 4.11.4, echo high > /sys/class/drm/card0/device/power_dpm_force_performance_level), thanks! But temperature of the card has jumped up from 50C to 70C.