Lenovo T530 randomly turns off when connected to external monitor-Collection of common programming errors

I’ve been experiencing a very strange problem on my Lenovo T530 on Ubuntu 12.04. The computer randomly shuts off with no warning. This seems to be completely random, although I’ve noticed that it only happens when I’m connected to an external monitor.

I’ve tried various things including installing various versions of my video drivers (I’m using NVidia drivers, version 319.32, but the problem happens on older versions as well). I’ve looked in /var/log/dmesg and /var/log/syslog but there appears to be no record of any problems. The laptop is normal temperature, and there is no indication that anything is wrong except that it just shuts off.

Has anyone seen this and have any additional tips of things I could try or places I could look for more information?

Here is sample output of the crash from the last -xwF command:

cory pts/0 :0.0 Thu Sep 26 19:19:57 2013 - crash (00:01)