How do I change the default graphics card on a Powermac G4 Quicksilver?

[Super Bisquit]

The last email I sent stated that the drm kernel module could not be built
because specialreg.h is an i386 only function.
I am also aware that the agp module needs drm to run. Why did I ask for
help? The PowerMac G4 Quicksilver has an agp graphics slot. I also know that
OpenFirmware is related to OpenBoot. If the default graphics slot can be
switched with OpenBoot, then why not with Open Firmware. The item I do not
have is the diagnostic tool. If the drm module cannot be built for the
machine in question, then what is the proper forth command for choosing a
PCI slot over the agp one without frying the logic board.

In the event that my request seems to be spam:
1) Whoever has the same machine can install the PowerPC snapshot 9.0 from
Nathan Whitehorn's site.
The proper howto is at the FreeBSD forums.
2) Try building the module from the 9.0 sources.
 The card is a radeon 200.