https://bugs.freedesktop.org/show_bug.cgi?id=82201
--- Comment #30 from Alex Deucher agd5f@yahoo.com --- (In reply to comment #29)
# echo "auto" > /sys/class/drm/card0/device/power_dpm_force_performance_level bash: echo: write error: Invalid argument
Not sure, what valid options would be for me.
auto, high, and low are the valid options. You are getting an error because the hw rejected your request.