Is there a way to use a ATX power supply with a G4 mother board that has the 27 volt power conector? I dont need that 27 volt connection to work as both my monotors are CRTs. For example the MDD or QS G4 im am thinking of buying one of those two mother boards for a mod project.

Its possible to use an atx for any of the powermacs, cept the G5. The MDD supplies are cheap on eBay and plenty efficiant to run anything you need. The QS can be modded with a wall wart to power that extra section of need power. It does work, but I do not necessarilly recommend that. I would stick with the MDD for doing a mod, they are the best of the best of the G4s. They beat most upgraded G4s with the stock dual 2mb cache processors. Some voltage tweaks and h20 and you would have a monster on your hands. By the way, I have seen a MDD out bench a G5 2.0 with those tweaks. I have owned both and sold my MDD for the latter G5. Good luck.