Well, assuming X is installed, you can check your /var/log/XFree86.0.log file to see why it didn't start. To try to fix the problem, you'll probably need to edit the /etc/X11/XF86Config-4 file. If you add something like this:
Code:
Section "Device"
Identifier "Standard VGA"
Driver "vga"
EndSection
and make sure that at the bottom in the "Screen" section, it reads:
Code:
Device "Standard VGA"
Then save and type gdm or kdm or startx or something... it should load the gui with the generic vga drivers. More long-term though, you might have to change the driver and tweak some of the settings. If you could post the "Device" section that's already in your XF86Config-4 file, that might help.