https://bugs.freedesktop.org/show_bug.cgi?id=102646
--- Comment #80 from Garrett dragonhart6505@gmail.com --- well...even better solution: install Radeon-Profile
sudo su cd /usr/bin radeon-profile
boom...manual control with the radeon-profile GUI...something i've not once seen mentioned in any tutorials. as long as you know what you're card is capable of, you can manually set clock percentages and a custom fan curve.
fan curve only stays active as long as radeon-profile is opened as far as i can tell