Ubuntu / Apple :: IBook Screen Just Goes Off Unexpectedly - Fix This?

I have been running Ubuntu in my iBook/g4 800, 12' inch screen since jaunty and I must confess that I have had a fair share of graphics issue, however, since karmic, my computer would just go off especially when the AC is disconnected then on plugging back the AC, it comes back on but with the windows or the previous items on the screen completely deformed, that kind of deformation you would only blame graphics for. So the deformation stays for long and a reboot is all I'm left with.While still in karmic, i thought an upgrade to Lucid would get things back in place but that never happened, so I have been wondering what to do. I thought of a key combination that would turn on the screen in an iBook but I cant seem to find that through google, so I'm left with just fixing the underlying issue which according to some post on the Internet, wrong graphics settings might cause the monitor to shut down unexpectedly. I don't know exactly what exactly am I supposed to do? If that post is anything to go by, here is my xorg.conf(I know karmic+ does not need this but my system needs it) code...