Ctrl+Alt+F1 combo doesn't work

Hi everybody,

I've got a network problem on my server, but I can't access to the system with a screen and keyboard connected, as each time I type a touch this is refreshing my screen. So I can't enter my login and password., or get the emergency screen. I already changed screen and keyboard without any positive effect.

With a LiveCD I configured a init 3 start, but I can't get any terminal screen, I've the passive syslog terminal only.

How can I get an entry to my system in this case?

Thanks for your help.....