First of all, we will see which outputs are available, connected/disconnected with xrandr –verbose command:
black@sysbuntu:~$ xrandr –verbose
Screen 0: minimum 320 x 200, current 1280 x 800, maximum 2720 x 900
LVDS connected 1280×800+0+0 (0×4f) normal (normal left inverted right x axis y axis) 0mm x 0mm
Identifier: 0×4b
Timestamp: 12612
Subpixel: horizontal rgb
Clones:
CRTC: [...]

I was trying to install new virtual machine (Ubuntu 8.10 Server – i386 ) on VirtualBox. After i install my O.S, while it was reebooting the system, my Ubuntu system stucked with the error:  ” Please use a kernel apropriate  for your cpu ” error.
After a while googling, i found how to solve this issue:
1. [...]

The following steps define how to setup OPENVPN Server side configuration on Debian Lenny, but do not forget that these steps are customized for the network scheme above. Therefore this documentation does not include default configurations at every stage.
1. Install Debian Lenny on your server. And be sure that you have two different nic available. [...]