This question already has an answer here:
- What should I do when Ubuntu freezes? 44 answers
I'm having a bit of instability lately, and while I've given up on fixing it (I thought I'd broken something irreparably in Quantal so I wound up upgrading to Raring for lack of any better ideas, so I have to live with a little bit of instability for now), it occasionally (once a week, often when I'm on a Skype call) happens that X stops refreshing, but all process continue to run properly in the background (music will keep playing until it reaches the end of a file, Skype continues to work, ssh processes keep going).
Is there any way for me to get X to start responding again at times like this? Normally I'd just let everything run out as best I can and then hard reboot, but I'm wondering if there's any way I can save it. Ctrl+Alt+F1 doesn't seem to have any useful effect -- it gets rid of X on one display, but I never get an interactive shell back.