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mectojic

macrumors 65816
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Dec 27, 2020
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I've read on Everymac that the earliest iBook Clamshells came loaded with Mac OS 8.6, not OS 9. Apparently, only the 300MHz models released prior to the release of OS 9 (so from July – approx. late October 1999) were shipped with Mac OS 8.6.

I know it's almost a trademark rule that Apple computers cannot run an earlier version than the one they shipped with... but was this true in 1999? Could later iBook Clamshells – the post-October 1999 300MHz models, as well as the higher MHz models (and other newer G3s) – install OS 8.6 from a CD/USB?

P.S. this is a similar problem to the iMac G4 15" 800Mhz models – without any change to specs at all, the earlier ones shipped with OS 9 installable, and later ones allowed OS X only, requiring a hacked installer for it to work.
 
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I've read on Everymac that the earliest iBook Clamshells came loaded with Mac OS 8.6, not OS 9. Apparently, only the 300MHz models released prior to the release of OS 9 (so from July – approx. late October 1999) were shipped with Mac OS 8.6.

I know it's almost a trademark rule that Apple computers cannot run an earlier version than the one they shipped with... but was this true in 1999? Could later iBook Clamshells – the post-October 1999 300MHz models, as well as the higher MHz models (and other newer G3s) – install OS 8.6 from a CD/USB?

P.S. this is a similar problem to the iMac G4 15" 800Mhz models – without any change to specs at all, the earlier ones shipped with OS 9 installable, and later ones allowed OS X only, requiring a hacked installer for it to work.
You can often get around OS limitations like this by overriding the hardware identifier and/or CPU type via Open Firmware.

I was able to get my Pismo to boot Mac OS 8.6 using @LightBulbFun 's techniques found here:

My Blueberry iBooks natively boot Mac OS 8.6, and I don't have any other Clamshells, so I couldn't confirm that it is going to work. Your best bet is to give it a shot!

P.S I actually had one of the Blueberry's out earlier today with my Sawtooth 8.6 restore disc, ready to reinstall the OS then got interrupted and put it back on the shelf... I must have been telepathically sensing this question coming! :apple:
 
You can often get around OS limitations like this by overriding the hardware identifier and/or CPU type via Open Firmware.

I was able to get my Pismo to boot Mac OS 8.6 using @LightBulbFun 's techniques found here:

My Blueberry iBooks natively boot Mac OS 8.6, and I don't have any other Clamshells, so I couldn't confirm that it is going to work. Your best bet is to give it a shot!

P.S I actually had one of the Blueberry's out earlier today with my Sawtooth 8.6 restore disc, ready to reinstall the OS then got interrupted and put it back on the shelf... I must have been telepathically sensing this question coming! :apple:
Would you mind posting the prim-info from your Blueberry iBook.

OS X:

Code:
ioreg -l | grep prim-info

Open Firmware: ( Best to use a telnet session )

Code:
dev via-pmu
dev powwer-mgt
.properties

If you install the PCIDDK3.0 the Mac OS you can use the DisplayNameRegistry tool to get that info too:

PCI_DDK_3.0.sit.hqx

Code:
Devices:device-tree:pci:mac-io:via-pmu:power-mgt
prim-info
 
I've read on Everymac that the earliest iBook Clamshells came loaded with Mac OS 8.6, not OS 9. Apparently, only the 300MHz models released prior to the release of OS 9 (so from July – approx. late October 1999) were shipped with Mac OS 8.6.

I know it's almost a trademark rule that Apple computers cannot run an earlier version than the one they shipped with... but was this true in 1999? Could later iBook Clamshells – the post-October 1999 300MHz models, as well as the higher MHz models (and other newer G3s) – install OS 8.6 from a CD/USB?

P.S. this is a similar problem to the iMac G4 15" 800Mhz models – without any change to specs at all, the earlier ones shipped with OS 9 installable, and later ones allowed OS X only, requiring a hacked installer for it to work.

all PowerBook2,1's (first gen clamshells) can Boot Mac OS 8.6, natively, regardless of what they originally shipped with :)

you just need to use an appropriate restore disk ie one for an iBook or later :) (I think the Sawtooth image is the last/latest Mac OS 8.6 version)

the first slot loading iMac's iMac2,1 can run Mac OS 8.6 natively as well for those curious

and the same for PowerMac3,1 Sawtooths (Sawteeth?), although watch out what GPU you have installed, the Mac OS 8.6 Tool Box ROM will hang and fail to load if you say have an NVIDIA GPU installed

(well a GeForce FX 5200+ at least, I should probably dig out my GeForce2 MX and 4 MX and see how Mac OS 8.6 reacts to that)


as a side note I wonder if there is a way to make Mac OS 8.6 boot with newer ToolBox ROM images, the latest for 8.6 is 2.5.1 IIRC which is rather limited in its hardware support

would be neat if we could use 10.2.1 or something!
 
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I have actually had tried doing this long ago. My iBook was manufactured in 2001, one of the last 32MB models. I got OS 8.6 to boot a few times, maybe 1/20. And one time it didn’t crash after booting for about 30 minutes, even played a video in QuickTime. But usually it always crashed within the first minute. Everything worked besides that, even WiFi. Just kept getting Finder bombs until the partition corrupted...

From my understanding, the firmware update makes it incompatible, and some hardware changes shipped in newer clamshells require that newer firmware.

I tried with the iBook and Sawtooth restore discs, both resulting in the same results mentioned above. Some iBooks can definitely not boot 8.6.
 
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This is quite remarkable (and sad) - on the other hand, I got 8.6 to boot on my 500 MHz Titanium PowerBook that shipped with 9.1. That was fun :)

I honstly think thats a bit of a Myth, on a machine that old, Panther/OS X cant just silantly install a BootROM update

you have to manually go put the machine into programmers mode etc etc and I have never heard of a Firmware update breaking an older compatible OS on an Apple machine


I have a later 64MB of RAM soldered onboard PowerBook2,1 clamshell I should throw 8.6 onto it and see what it does :)
 
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