https://bugs.freedesktop.org/show_bug.cgi?id=55692
--- Comment #45 from Serkan Hosca serkan@hosca.com ---
Thats cool. I found out what triggers the gart error. I had gtk-redshift on session start up. After removing that the ttm error is gone. It redshifts the screen colors so that it is easy on the eyes and when its started it starts the redshifting gradually.
Scratch that, i removed redshift but the gart error happened again. Its not the gdm startup though, it happens during gnome session startup.