Thaks topdog for quick reply !
The system could restart before the install tje ISPconfig with GUI Mode without any problem .
I have a look at the inititab conf file and seem to be ok starting with init5 .
I can see a blue screen from gnome starting but I never get the gnome logon screen . I press crtl Alt F5 to start with text mode .
Second I try to boot with interactive mode and not starting the ISPconfig to see if I could get in but still the same problem .
very strange . I tried to set up twice with really fresh install and got the same problem .
Any ideias ?