/etc/xorg.conf
As root, open that in a text editor like Emacs or Vim, and look for the resolution portion. Been a while for me asI haven't installed an OS in almost a month so I'm not positive what part of it it was I edited.
Another thing you could do:
/etc/inittab
Open that up and switch the default run level from 5 to 3 and run Sax2
