Apparently this problem is already known:
http://ubuntuforums.org/showthread.php?t=1613132
Since I'm able to boot to a shell, what I just did was to add nomodeset to /etc/default/grub and run update-grub, as described on the ubuntuforums page above. So now the altered line in /etc/default/grub looks like
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash nomodeset"
Apparently this problem is already known:
http:// ubuntuforums. org/showthread. php?t=1613132
Since I'm able to boot to a shell, what I just did was to add nomodeset to /etc/default/grub and run update-grub, as described on the ubuntuforums page above. So now the altered line in /etc/default/grub looks like
GRUB_CMDLINE_ LINUX_DEFAULT= "quiet splash nomodeset"