Comment 2 for bug 1008494

Same problem here. Started after upgrade to 12.04.
Suddenly the screen goes black, and after a while the login screen is shown. All running applications are killed.

Syslog:
Jun 8 08:22:17 mask-i7 kernel: [236510.328432] NVRM: Xid (0000:01:00): 6, PE0001
Jun 8 08:22:18 mask-i7 gnome-session[2072]: Gdk-WARNING: gnome-session: Fatal IO error 11 (Resursen tillfälligt otillgänglig) on X server :0.#012
Jun 8 08:22:18 mask-i7 bluetoothd[1139]: Endpoint unregistered: sender=:1.47 path=/MediaEndpoint/HFPAG
Jun 8 08:22:18 mask-i7 bluetoothd[1139]: Endpoint unregistered: sender=:1.47 path=/MediaEndpoint/A2DPSource
Jun 8 08:22:18 mask-i7 bluetoothd[1139]: Endpoint unregistered: sender=:1.47 path=/MediaEndpoint/A2DPSink
Jun 8 08:22:19 mask-i7 acpid: client 1278[0:0] has disconnected
Jun 8 08:22:19 mask-i7 acpid: client 1278[0:0] has disconnected
Jun 8 08:22:19 mask-i7 acpid: client connected from 13054[0:0]
Jun 8 08:22:19 mask-i7 acpid: 1 client rule loaded
Jun 8 08:22:20 mask-i7 acpid: client connected from 13054[0:0]
Jun 8 08:22:20 mask-i7 acpid: 1 client rule loaded
Jun 8 08:22:24 mask-i7 rtkit-daemon[2001]: Successfully made thread 13176 of process 13176 (n/a) owned by '117' high priority at nice level -11.
Jun 8 08:22:24 mask-i7 rtkit-daemon[2001]: Supervising 1 threads of 1 processes of 1 users.
Jun 8 08:22:25 mask-i7 rtkit-daemon[2001]: Successfully made thread 13178 of process 13176 (n/a) owned by '117' RT at priority 5.
Jun 8 08:22:25 mask-i7 rtkit-daemon[2001]: Supervising 2 threads of 1 processes of 1 users.
Jun 8 08:22:25 mask-i7 rtkit-daemon[2001]: Successfully made thread 13179 of process 13176 (n/a) owned by '117' RT at priority 5.