Thanks! As I suggested in the original bug description "radeon.agpmode=-1" works as boot option. But as it's a bug and I didn't find an up-to-date bug description I filed one. I am sure this affects some more users of Apple PPC hardware.
Interestingly enough my Powerbook 5,8 is not affected by this bug though it is equipped with a very similar r300-class graphics board! "ATI Radeon Mobility 9600/9700 (M10/M11) NP (AGP)", (ChipID = 0x4e50).
@Martin:
Thanks! As I suggested in the original bug description "radeon.agpmode=-1" works as boot option. But as it's a bug and I didn't find an up-to-date bug description I filed one. I am sure this affects some more users of Apple PPC hardware.
Interestingly enough my Powerbook 5,8 is not affected by this bug though it is equipped with a very similar r300-class graphics board! "ATI Radeon Mobility 9600/9700 (M10/M11) NP (AGP)", (ChipID = 0x4e50).