I was able to finally get the GUI back by doing this:
sudo apt-add-repository ppa:ubuntu-x-swat/x-updates
sudo apt-get update
sudo apt-get install nvidia-current
Now, how can I get the headless computer to boot xterm without an actual monitor?
I tried changing my xorg.conf to:
Changing the xorg.conf made failed startx with the error: no screens
Section "Device" Identifier "Onboard Intel Graphics" Driver "vesa" EndSection Section "Monitor" Identifier "Generic Monitor" HorizSync 31-101 VertRefresh 60-160 EndSection Section "Screen" Identifier "Basic Screen" Monitor "Generic Monitor" Device "Onboard Intel Graphics" SubSection "Display" Modes "1024x768" EndSubSection EndSection
Any ideas how to make Ubuntu 12.04 headless and make startx/xterm work?