After further analysis I believe the problem is in the integrated video: nvidia 6150se nforce 430.
This problem occurs both using Ubuntu 13.10 Unity and Ubuntu-gnome 13.10
When I installed nvidia-304 proprietary program it doesn't happen.
So the bottom line is nouveau is the problem area and needs attention.
After further analysis I believe the problem is in the integrated video: nvidia 6150se nforce 430.
This problem occurs both using Ubuntu 13.10 Unity and Ubuntu-gnome 13.10
When I installed nvidia-304 proprietary program it doesn't happen.
So the bottom line is nouveau is the problem area and needs attention.