Created attachment 103340 [details]
At times the graphics locks up. In one of five times the mouse pointer still moves, three out of five times the system recovers and 2 out of five times the system crashes and reboots.
Created PR according to the message in the syslog.
$ uname -a
Linux Cassandra 3.13.0-32-generic #57-Ubuntu SMP Tue Jul 15 03:51:08 UTC 2014 x86_64 x86_64 x86_64 GNU/Linux
$ X -version
X.Org X Server 1.15.1
Release Date: 2014-04-13
X Protocol Version 11, Revision 0
Build Operating System: Linux 3.2.0-37-generic x86_64 Ubuntu
Current Operating System: Linux Cassandra 3.13.0-32-generic #57-Ubuntu SMP Tue Jul 15 03:51:08 UTC 2014 x86_64
Kernel command line: BOOT_IMAGE=/vmlinuz-3.13.0-32-generic root=/dev/mapper/ubuntu-root ro vesafb.invalid=1 splash quiet nopat vt.handoff=7
Build Date: 16 April 2014 01:36:29PM
xorg-server 2:1.15.1-0ubuntu2 (For technical support please see http://www.ubuntu.com/support)
Current version of pixman: 0.30.2
Before reporting problems, check http://wiki.x.org
to make sure that you have the latest version.
*** This bug has been marked as a duplicate of bug 54226 ***