PowerBook6,4 (1.33Ghz) - Odd Display Issue on OS 9

[kgllewellyn]

Greetings!

So I have a PowerBook6,4 12" 1.33Ghz with the Nvidia GeForce FX Go 5200. Now I'm well aware that this GPU is not supported under OS 9 for 3D acceleration and other people have reported it being stuck on 256 colors under Mac OS 9. Here's the curious part though, when I booted it up from the OS 9 Universal iMic CD, it is booted with Millions of Colors. However when booted from Hard Disk it is stuck on 256 colors. I am unable to make any changes to bit-depth once the system is booted however, nor the resolution.

I was thinking whether it was an extension on the CD that was causing it to be booted in Millions, but even after copying the entire contents of the CD and booting from Hard Disk it would still only be in 256 colors.

So this leads me to believe that the act of booting between the CD and HD is changing something, but I'm not sure what.

I'm going to try and use SwitchRes to see if I can force the machine to change bit-depth and resolution and I'll report back my results.

Is there any changes we can make to OpenFirmware or the ROM file that will ensure that the correct display capabilities of this machine is reported to OS 9. This obviously isn't controlled by extensions as even when extensions are disabled machines are still able to change between bit-depth and resolution; I'm figuring it's something going on in the Mac OS ROM file?

Any insight is greatly appreciated.

Apart from that, Sound, Ethernet, USB work great on this. Airport and Bluetooth obviously not working.

Cheers,

Kai

[kgllewellyn]

Hey,

So further update to this. Unfortunately, SwitchRes will only switch resolutions/bit-depth depending on what is presented to the system as supported. There doesn't seem to be a way to 'force' a specific mode.

Further note of interest. If I boot this machine up with the mini-DVI adaptor connected to an external display, it displays at its native resolution and in millions of colors, unlike the internal display which continues to be 256 Colors @ 1024x768.


Took a screenshot of this setup in Monitors. As you can see, there's no options to change settings. Does anyone know how to adjust what is presented to the system as being a supported display mode. It appears that it is only marking what the displays are booting up as as supported and isn't properly polling them. Perhaps, is there a way of forcing the OS to display in a certain mode? It obviously seems like the modes are supported by the graphics chipset in OS 9, but there just doesn't seem to be a way to change them once booted.


I know iMic made some changes when doing his iBook G4 release of the Mac OS ROM that it allowed people to switch resolutions and bit-depth, and I'm wondering if similar modifications can be done to get this working on the PowerBook6,4?


Thanks

[Greystash]

It's definitely a driver thing/unsupported NVIDIA card. I had the same problem with the 15" and 17" PBG4's, darthnVader sent me a modified ATI NDRV but I'm not sure if this can be done for the NVDIA drivers. I don't think the later OSX drivers contained NDRVs so you may be out of luck regarding this method.

However, if I booted into OSX and changed the color depth + resolution etc. these settings would persist when booting into OS9. If you can figure out where this information gets stored/if it's accessible within Open Firmware you could write some scripts (maybe Applescript) that modify or change an Open Firmware boot script to set the desired values and then reboot.

My post regarding this problem:
http://macos9lives.com/smforum/index.php/topic,4593.0.html

Code: [Select]

http://macos9lives.com/smforum/index.php/topic,4593.0.html
Here's an example of my Open Firmware boot script which turns the fans on at boot:

Code: [Select]

\ comment
cr
dev /cpus/PowerPC,G4@0
80010201 encode-int " cpu-version" property
device-end
" fan" open-dev constant fan-ih
1 3B6 " set-speed" fan-ih $call-method
2 3B6 " set-speed" fan-ih $call-method
boot hd:,\\:tbxi

To get this script running automatically at boot you need to set the boot device to the script. Run this within Open Firmware:

Code: [Select]

setenv boot-device hd:\bootscript
Good luck, hopefully there are some other ideas out there.

[kgllewellyn]

Thanks for your reply!

I don't suppose darthnVader would be able to share how he was able to port NDRVs over from OS X to OS 9? Are these too complicated to be made from scratch?

Sadly the OS X settings do not appear to persist into OS 9. Something else is changing it on the OpenFirmware side to 256/1024x768. Not sure how I'd go about specifying the correct values to OF.