I too am seeing the very same symptoms, it's happened several times. Machine is a Thinkpad T60 with Radeon Mobility X1400. I have KMS turned off with a kernel option because it was causing a lot of problems.
Xorg.0.log contained "[mi] EQ overflowing. The server is probably stuck in an infinite loop." and a stack trace implicating radeon_drv.so and libglx.so. Next time it happens I'll make sure to keep a copy of the stack trace. Also syslog contains: May 30 20:36:30 jarvis kernel: [60546.074216] Uhhuh. NMI received for unknown reason b0 on CPU 0. May 30 20:36:30 jarvis kernel: [60546.074222] You have some hardware problem, likely on the PCI bus. May 30 20:36:30 jarvis kernel: [60546.074225] Dazed and confused, but trying to continue Seems to happen after a day or so of use, possibly always after a suspend/resume. Suddenly the pointer goes slow and no input works, not even the likes of ctrl-alt-delete nor ctrl-alt-f1. Since GLX is implicated I'm trying turning off compositing to see if it happens again. -- [Radeon] [Lucid] [mi] EQ overflowing. The server is probably stuck in an infinite loop https://bugs.launchpad.net/bugs/567696 You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs