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I read and tried this and it doesn't work for me!

when I type

echo "mid" > /sys/class/drm/card0/device/power_profile

I see what this value really changed (needs the chmod was applied before, that is missed in the text), when i type 'cat /sys/class/drm/card0/device/power_profile'.

But when I check again

cat /sys/kernel/debug/dri/0/radeon_pm_info

I see no changes! Frequencies are still at max. And yes,


is set to 'profile' (not 'dynpm').

How can I change frequencies?! Ubuntu 12.04, Radeon 6850.

share|improve this question
You need to run that command as root, in other words, sudo -i, and then echo "mid" > /sys/class/drm/card0/device/power_profile. Run exit when done. – mikewhatever Aug 30 '12 at 15:45
of course I need root! but if I said that profile was really changed, so I've had it. the problem is that it didn't affect gpu frequencies :( – Vladimyr Aug 30 '12 at 17:35

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