I have Ubuntu 10.04 running on a Dell laptop/Nvidia video. Everything works fantastic, except for one "nit" that is VERY annoying.. Every so often the graphical interface stops responding, such that the following happens: any gnome-terminals I happen to have open are still working normally, if I have Audacious running, the music continues to play, but all Gnome panels no longer respond, I cannot drag any open windows around, but I can right-click on the desktop and get that Gnome menu, but none of the menu selections respond. The first time this happened, I had to powercycle the laptop, as I didnt have any shell-window open.. It was then I discovered that Ubuntu now disables the ctl-alt-bksp/X restart. I've since re-enabled it, and an X restart restores the gui. This happens often at least once a day, and since I use the laptop daily, it becomes annoying to lose the apps I had running when I have to restart X. I've tried checking dmseg/syslog/messages immediately after this happens, but have not spotted any "smoking-gun" pointing to why this is happening. I first thought it might be Compiz causing it, so I disabled it, still happened. Since the laptop has Nvidia 8400M video, I use the Nvidia closed-source "blob" driver.. I'm posting here to see if 1) anybody else is seeing this, 2) where I should be looking for the cause....
Thanks
~/.xsession-errors
is a place to look for culprits – msw Sep 25 '10 at 21:16