Comment # 61 on bug 93826 from Pavel Bordukov

(In reply to Alex Deucher from comment #60)
> Created attachment 131983 [details] [review] [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.