Everything works fine disabling dpm on amdgpu. 

Workaround steps: 

edit /etc/default/grub

add amdgpu.dpm=0 to GRUB_CMDLINE_LINUX=

generate new config: 

sudo grub2-mkconfig -o /boot/grub2/grub.cfg

reboot (to test new permanent config is done. 

You will notice now
/sys/class/drm/card0/device/power_dpm_force_performance_level doesn't exist. 

For months I though the problem was somewhere else, and was looking for many
combinations without success, without this workaround I had a very annoying
experience working, playing videos, whatever, because randomly I had freezed
display and had to restart. I couldn't play any game before, now tested with
many games and everything is perfect. 

Could be good to apply this workaround by default? so users doesn't experience
the annoying bug?