Last night I was trying to make it so my iPod Touch would interface with my Kubuntu machine, and somehow I ended up doing something very, very wrong. Now, whenever the computer starts up, before GRUB even loads, I get a few strange error messages:
[drm] Nouveau - Couldn't find matching output script table.
GPU Lockup
(Those aren't the exact errors, I had to shorthand transcribe the gist). Not only do those errors (and others that are mostly identical) occur, but part of the way through the boot process my screen turns to this (and is afterward useless until the power is hard-reset :/):

Does anybody have any idea as to what I did? I've been trying all day to get anything working using a Xubuntu LiveCD, but to no avail. I even erased all of my data trying to perform a clean install from the disc.

Hit <f2> for this or <esc> for that.Once that passes, if I have it set to boot from the hard drive, it hangs for a moment and then goes to the screen I posted. – Andy Sep 22 '10 at 21:08