View Full Version : Need to switch from agp to isa-pci for graphics.

Nov 21, 2010, 10:39 PM
PowerMac G4 933MHz agp slot. I have Debian 5.x and FreeBSD 9.0 on the machine. The modules of agp and drm build only from current. With agp, this is not a problem; however, drm will not build due to a dependency on x86. Discussions on the freebsd-ppc mailing lists state that drm is unstable.
The machine came with a Matrox card and the standard radeon. There is support for the Matrox with both OSes but I do not know how to switch the default graphics card in OpenFirmware. How do I do this from the forth prompt?

Dec 1, 2010, 01:15 AM
I take it that no one knows how to do this from the forth prompt?
The forth prompt is the open firmware prompt.

occams razor
Dec 1, 2010, 01:18 AM
Have you tried removing the agp card when booting or installing to force it to use the other card?

Dec 1, 2010, 07:41 AM
It didn't work but, a genuine thanks for the help.

occams razor
Dec 1, 2010, 08:49 AM
Well it was worth a shot. Good luck on trying to get it

Dec 1, 2010, 02:12 PM
i don't have one to experiment with right now, but think the 'pull the AGP card' was the correct answer. after pulling the card, i think you would need to reset PRAM to get it to pick up the change. the video card/settings are stored in PRAM

PRAM stores certain system and device settings in a location that Mac OS X can access quickly. Exactly which settings are stored in the computer's PRAM varies depending on the type of computer as well as the types of devices and drives connected to the computer. Parameter RAM is a small area of non-volatile RAM (NVRAM).

Some information stored in PRAM includes:

* Display and video settings such as refresh rate, screen resolution, number of colors...

you can reset NVRAM and PRAM from open firmware using;

0 > reset-nvram
Press Return
0 > reset-all
Press Return

The reset-all command should restart your Mac. If so, you have successfully reset the Open Firmware settings. best of luck.

occams razor
Dec 1, 2010, 10:50 PM
Keep us updated. I would love to know how it works out