Worked this out with Dell support. Apparently a common problem with Dell Precision M6500, but not sure of the reasoning. Problem was resolved by replacing motherboard and video card (under warranty). Hope this helps someone else with this problem!
** Changed in: xorg (Ubuntu) Status: New => Invalid -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1071050 Title: Dell Precision M6500 with NVIDIA Quadro FX 3800M crashes when using OpenGL screensaver To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xorg/+bug/1071050/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs