https://bugs.freedesktop.org/show_bug.cgi?id=76490
--- Comment #23 from dex+fdobugzilla@dragonslave.de --- I did some checks using the old profile based aproach for PM and switched between the states.
Following are the data from /sys/kernel/debug/dri/0/radeon_pm_info when switching via echo X > /sys/class/drm/card0/device/power_profile
Default: ================================= default engine clock: 1080000 kHz current engine clock: 149990 kHz default memory clock: 1400000 kHz current memory clock: 149990 kHz voltage: 1206 mV PCIE lanes: 8
Low: ================================= default engine clock: 1080000 kHz current engine clock: 299990 kHz default memory clock: 1400000 kHz current memory clock: 149990 kHz voltage: 875 mV PCIE lanes: 8
Mid: ================================= default engine clock: 1080000 kHz current engine clock: 299990 kHz default memory clock: 1400000 kHz current memory clock: 149990 kHz voltage: 875 mV PCIE lanes: 8
High: ================================= default engine clock: 1080000 kHz current engine clock: 1080000 kHz default memory clock: 1400000 kHz current memory clock: 1399990 kHz voltage: 1206 mV PCIE lanes: 8
The last state (high) results in immediate freeze.