This is a command-line tool for changing the power saving settings of the open-source radeon X.org driver for AMD Radeon HD graphics cards.
If your video card fans are making too much noise, this command will quiet them down.
If you want to play video games or do another graphics-intensive task, this command will give you all juice your card has.
The tool includes a systemd unit file that you can use to set your graphics card's power settings at boot time.
systemctl enable radeonhd-power.service systemctl start radeonhd-power.service
This review request will make the tool available as a Fedora package, so the command below will install it.
yum install radeonhd-power
The tool is Copyright (c) 2012-2013 Victor Costan, and distributed under the MIT license.