My wife's computer has the same problem. She is using the k7 kernel and nvidia driver from repos. Her computer started crashing randomly after updating to Dapper.
On her last crash, I logged on to her computer via ssh, ran 'top', 'xorg' was running at 99.9% of her cpu speed. It has happed while running Firefox, Gimp, and serval other standerd apps. -- Xorg process freezes, uses 100% of CPU. Can be killed by remote terminal. https://launchpad.net/bugs/51991 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
