Getting rid of Catalyst

Lately I’m getting really annoyed with the ATI drivers and the system instability it gave me. I posted my problems on our mailinglist but what can I do about it? Not much.

So I decided to take a look, once again, to the state of the Opensource ATI driver and made it work with the stock Entropy packages we have.

Let me warn you that if you are happy with current fglrx, don’t change it. If it ain’t broken don’t fix it!
Now if you are a bit of an experienced user and know how to revert some steps here is a small guide how to make things work for you.

Step 1: Get rid of ATI drivers
equo remove ati-drivers

Step 2: Let the kernel load the radeon module
Edit /etc/conf.d/modules and add modules=”radeon” at the end of the file

Step 3: Remove some kernel parameters from the grub menu
Edit /etc/default/sabayon-grub and remove the console=tty1 quiet splash= and vga= completely.

Step 4: Add a custom parameter that enables KMS (Kernel Mode Setting)
Edit /etc/default/grub and add radeon.modeset=1 to the GRUB_CMDLINE_LINUX_DEFAULT variable

Step 5: Regenerate your grub.cfg file:
grub-mkconfig -o /boot/grub/grub.cfg

Step 6: Use “ati” in /etc/X11/xorg.conf
Edit /etc/X11/xorg.conf and change “fglrx” to “ati” in the Driver section of the file
Now reboot.

Optionally you can also play around with the new Gallium3d implementations. To change things to use gallium3d instead of the older mesa you can use the command: eselect mesa list to show how things are currently set.

In my case: eselect mesa set r600 2
Would set it to use gallium3d

Some reading:
http://en.wikipedia.org/wiki/Gallium3D
http://en.wikipedia.org/wiki/Kernel_mode-setting