My X server seems to be faulty, but I don't know why. I had some problems last week with a new motherboard, but they seemed to be resolved. Today, I updated Kubuntu and restarted, but my Viewsonic VX900 LCD monitor shows the splash screen for several seconds, then displays the message "Out of Range"

I have tried various kernels in Grub, some in recovery mode, most do the same thing. No key combinations bring up a shell prompt like I expect.

The one exception was a very old kernel, that would only mount the file system as read-only, so I can't fix up the xorg.conf file.

Is there anything to be done?