Comment 1 for bug 212434

I have upgraded Xubuntu from 7.10 to 8.04, and I occasionally have the same problem. I need to killall gdm to shut down the X server from a normal terminal (CTRL+ALT 1), or simply do a sudo reboot. As it doesn't happen 100% of the time, I suspect that the suspend mode has something to do with it. The last time this phenomenon occured, my laptop had resumed operation from stand-by mode. I will report back with better statistics when I have them.