0005911: [drm:i915_hangcheck_elapsed] *ERROR* Hangcheck timer elapsed... GPU hung

I have a brand new Dell Optiplex 7010. It was initially delivered with Ubuntu 11.10, but reinstalled with CentOS. Every other day or so, the screen locks up for a few seconds, then I can see this in the kernel log:<br /> <br /> [drm:i915_hangcheck_elapsed] *ERROR* Hangcheck timer elapsed... GPU hung<br /> [drm] capturing error event; look for more information in /debug/dri/0/i915_error_state<br /> <br /> Then, the graphics in some applications (including Firefox and Emacs) are distorted.