(In reply to Shmerl from comment #29)

> Which one exactly did you set it at?
> 
> I have 2560x1440 / 144 Hz monitor (LG 27GL850) and Sapphire Pulse RX 5700 XT
> (hardware switch set to higher performance BIOS) and in general I noticed a
> similar thing. During normal idle KDE operation, power stays at around 32 W
> or so.
> 
> If I suspend and resume, power drops to 11 W and the monitor starts
> flickering wildly. I tried to do:
> 
> echo "low" > /sys/class/drm/card0/device/power_dpm_force_performance_level
> 
> But that didn't really help with flickering.

You may have to first set it to "high", then back to "low".

It will also stop working once a fix that adds "smu->disable_uclk_switch = 0;"
in amdgpu_smu.c filters down to the mainline kernels.