For me, I did the 'sudo Xorg -configure' command to get an xorg.conf, then adjusted it to have: Section "Device" ... Driver "radeon" Option "AccelMethod" "EXA" EndSection
For me, I did the 'sudo Xorg -configure' command to get an xorg.conf, then adjusted it to have:
Section "Device"
...
Driver "radeon"
Option "AccelMethod" "EXA"
EndSection