In order to get Mac OS X 10.3 installed on my 'Sawtooth' (AGP) G4, I had to remove the GeForce2MX card that I had flashed with an Apple ROM image. Details about why it didn't work are here, it looks like Apple may have removed some support from their driver.
Things are working well with the original 16MB ATI card back in the machine, but I don't get all the cool Quartz Extreme stuff like I did under 10.2.
Oh well.
