I'm using Ubuntu 12.04.1, 64 bits, installed on a Z77 Pro4 (ASrock motherboard), crucial M4 SSD drive (sata 3), and intel i5 3570k (ivy bridge).

I have this annoying problem : When I startup the computer, I get a CLI login prompt :

At this moment, if I press enter, i get the usual CLI login prompt. If not, here is what I get :

From now, if I login using CLI, i identify the lightdm processus, kill and start it :

#ps -A | grep lightdm
#sudo kill -9 1273
#sudo lightdm

and miracle, these commands bring back the gui login screen. BUT It's very annoying as I have to repeat these steps at every boot, and the people using this desktop are not familiar with linux at all!

So I tried to figure out the cause and here is what I found : If, when I shutdown the computer, the WGA cable is not pluged in, then Ubuntu will boot on GUI login screen without a glitch!

But If the WGA cable is pluged in when shuting down, I will get CLI login prompt...

Note 1: I installed linux kernel 3.4, but it hasn't solve the problem.

Note 2: Is it linked to the new HD 4000 integrated graphic processor ?

Note 3: If i boot on an USB stick (Ubuntu 12.04), NO problems !

Note 4: If booting on the SSD, when clicking "shutdown" button, the shutdown process never ends up (logout screen keep displaying and fans are still rolling). But if booting on USB stick, the shutdown action runs properly.