Hey there,
I recently picked up a Power Mac G5 with a Radeon X800. Nice lil card. However, the version of ATI Displays that ATI is distributing on their site does not support the X800. Version 4.4.4, which is on the X800 retail CD, does.
If you've got an X800 and wouldn't mind throwing the installer from the CD in my direction, please grab me on AIM.
Thanks.