I’ve been having this problem lately:
My Fedora 20 would freeze; after a while, while using the xorg-x11-drv-ati driver.
Another thing I noticed, was the fan of the card going up and up like crazy.
First thing I did, was install lm_sensors:
yum -y install lm_sensors
And ran the sensors command:
$ sensors radeon-pci-0100 Adapter: PCI adapter temp1: +85.5°C (crit = +120.0°C, hyst = +90.0°C) k10temp-pci-00c3 Adapter: PCI adapter temp1: +38.6°C (high = +70.0°C) (crit = +90.0°C, hyst = +85.0°C)
Wow! 75.5 ºC on my AMD/Ati card! I know why the freezes happen now! It overheats and crashes!
So, I’ll do what you need to do when you have problems: RTFM!
Now, there is a hint right there. You can try and control the power profile; but that is not exactly it. You want the system to do it for you. My answer was enabling dpm; by adding radeon.dpm=1 to the kernel line at /etc/grub2-efi.conf (in my case).
So, it looks something like this:
linuxefi /vmlinuz-3.12.9-301.fc20.x86_64 root=UUID=6c9b3ffd-c911-4dcb-9425-e44841ab379d ro rootflags=subvol=root vconsole.font=latarcyrheb-sun16 rhgb quiet LANG=en_US.UTF-8 radeon.dpm=1 initrdefi /initramfs-3.12.9-301.fc20.x86_64.img
Ok, now, the next thing is to rebuild my initrd image with dracut; which proved to be really easy:
su - dracut --force
Basically, if you don’t do that, you will be dropped to a shell when booting; just exit that and you’re good.