I'm seeing the same behavior (screen freeze, mouse still movable) from nvidia. Still nothing interesting in the xorg log, but here's the end of my dmesg:
[ 3361.843042] NVRM: Xid (0000:05): 9, Channel 00000000 Instance 00008069 status 0000001d [ 3361.844898] NVRM: Xid (0000:05): 9, Channel 00000020 Instance 00000000 Intr 00100000 Card is NVIDIA Corporation C51 [GeForce 6150 LE] (rev a2) The freezes were fewer after updating to kernel 3.4.0-030400-generic, but they still happen. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/994203 Title: Xorg freeze with Nouveau drivers To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xserver-xorg-video-nouveau/+bug/994203/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
