while browsing randomly screen goes black and logs me out

[giorgos]

The last few days while browsing and I think while I am clicking on something screen goes black and logs me out, this happens randomly.

ProblemType: Bug
DistroRelease: Ubuntu 11.10
Package: gdm (not installed)
ProcVersionSignature: Ubuntu 3.0.0-17.30-generic-pae 3.0.22
Uname: Linux 3.0.0-17-generic-pae i686
NonfreeKernelModules: nvidia
ApportVersion: 1.23-0ubuntu4
Architecture: i386
Date: Sat Mar 31 14:52:19 2012
InstallationMedia: Ubuntu 11.10 "Oneiric Ocelot" - Release i386 (20111012)
ProcEnviron:
 PATH=(custom, no user)
 LANG=el_GR.UTF-8
 SHELL=/bin/bash
SourcePackage: gdm
UpgradeStatus: No upgrade log present (probably fresh install)

[dino99 (9d9)]

This version has expired