MacOS 8.6 on "Sawtooth" G4

Hm? My Sawtooth came with 9.02 (which crashes left, right and centre, BTW).

Is there any way to get 8.6 running on the G4 using these CDs or am I basically screwed without the original?

Click to expand...

AFAIK, that's a version unique to the sawtooths, which came out after 8.6 was released & needed an updated 8.6. They run terrifically well with it (My mother's G4/500 is a strangely zippy beast with it, and I think I'll take it back to 8.6 if she ever upgrades to another machine)

Dana

According to Mactracker, the sawtooth did come with 8.6 originally, but later came with Mac OS 9.0. It also says it needs Mac OS ROM 2.5.1.

I would love a sawtooth running 8.6 It would be hella fast. Next to 9.2.2, if the hardware can run it, I run 8.6 on it; unless it can run 7.6.1.

I have a 8.6 multi install CD, it has installers on it for the Powerbook G3 Series (wallstreet), Powerbook G3 (Bronze), iMac, and PowerMac G3 (Blue & White). No specific G4 installer, but there is the generic installer as well as an updater file.

-digital

Got the 2.5.1 ROM? I searched hi and lo for it

I tihnk the ROM would do the trick here, hm?

so generic OS8.6 install + 2.5.1 ROM would boot the sawtooth?

Thanks for all the responses. [] ]'>

The ROM on my B&W G3 CD is 1.4, and on the 'retail' CD it is 1.6. Unfortunately neither one will boot my G4.

When running the generic OS 8.6 install application I get the error "this program will not run on your computer". This makes sense because the CDs contain install files dated prior to September 1999 when the G4 was released.

So, if I can somehow get a hold of a 2.5.1 ROM then yes, I should be able to boot up. However, I have no idea how to obtain it without actually locating a copy of an original G4 restore CD.

Joo think it would work with the ROM from OS 9.0 Sawtooth CD?

It doesn't work with the ROM from 9.0 I tried it.

I've asked a bunch of people selling sawtooth G4s on eBay whether they're willing to sell me their original restore CD. Although it seems that most G4s ended up shipping with MacOS 9. I think it is only the 400 and 450 mhz versions that had 8.6.

If I get a ROM that works I'll let you all know.

Thank you, almeath!

Everyone I have asked says that they either don't have the original install CD or that it came with OS 9. All the copies of 8.6 floating around the net are March 1999 retail copies that don't include the correct ROM. [] ]'>

Looks like I'll have to be realistic and accept that I can't get 8.6 running, at least for now.

I'm currently using 9.2.2. Maybe if I downgrade to 9.0.4 some of my older games might work better...

Good news: I got a hold of ROM 2.5.1, on an installation CD for a G4 system. [] ]'>

Bad news: The CD won't boot my G4! [xx(] ]'>

According to the system profile my machine is a 400mhz AGP based G4 with 20GB drive and ATI Rage 128. MacTracker lists the machine type as "406" and says it will run MacOS 8.6 with ROM 2.5.1

So, not booting with the CD, or even allowing me to install the OS at all (same "this program will not run on your computer" message) is really strange. The CD does not recognize the system it was designed to run on.

Could this be caused by a firmware update? Or the fact that MacOS X had previously been installed on the machine? I somewhat doubt it because I wiped the HD clean in order to reinstall MacOS 9.

Any ideas?

Might be a firmware update, yeah.

You might be able to instal directly in Open Firmware.

I'd go with a firmware update. Its unlikely that OS X would have anything to do with it - despite the fact that I primarily run my iMac under Mac OS X, it will quite happily boot of a retail OS 8.5 CD, which pre-dates my Rev. D iMac by several months.

I see there was a firmware update listed for the sawtooth G4s in 2001. It says it is for improved compatibility with OS X. I'll need to learn how to use Open Firmware to see if that update has been applied.

I still think its strange that a firmware update would render one's restore CD useless? It's the kind of thing you'd think Apple would mention in the ReadMe.

BTW, is there any way to reverse a firmware update? i.e. revert to factory default settings? [?]

[] ]'>

Try install another Mac OS 8.6 with MacOnMac on the SawTooth, and put the 2.5.1 ROM in the new installed system afterwards...

[] ]'>

And... can I have the.. well you know. [}] ]'>

Thanks for all the responses. [] ]'>
The ROM on my B&W G3 CD is 1.4, and on the 'retail' CD it is 1.6. Unfortunately neither one will boot my G4.

When running the generic OS 8.6 install application I get the error "this program will not run on your computer". This makes sense because the CDs contain install files dated prior to September 1999 when the G4 was released.

So, if I can somehow get a hold of a 2.5.1 ROM then yes, I should be able to boot up. However, I have no idea how to obtain it without actually locating a copy of an original G4 restore CD.

Click to expand...

I think just getting the ROM may not be enough. I remember that the beige G3 required MacOS 8, but shipped with a unique version specific to those models originally so retail 8.0 didn't work because it was released ahead of the G3's. Even IF you do have the ROM version required, you're probably going to have to hunt down a copy of the system disc that shipped with the early Sawtooths OR burn a copy of the install disc that you do have and do some tinkering to the files to force it to install on an unsupported machine.

To save you from endless speculation about the ROM version currently in your Mac, and which ROM that might be, you could go to Production information at the foot of the System Profile tab in Apple System Profiler 2.1.2 or later and see what Boot ROM version tells you.

Then go to this page for the difference between Mac OS ROM and bootROM, and here for more gen about what goes with what.

de

Thanks to everyone for their comments and suggestions.

This is what I've found:

Machine ID: 406

ROM Version: $77D.45F6

MacOS ROM file Version: 8.4

The ROM is apparently the same one used on the B&W G3 and many G3 iMacs.

I'm going to try installing 8.6 (my generic retail copy) on a disk image using SheepShaver, and then I'll drop the 2.5.1 ROM into the system folder and copy it across to a separate partition on my G4.

I'll report back on how this goes...

I've got 8.6 running on my 400 MHZ sawtooth. In college, I found a G3 Powerbook restore cd. I mounted the ASR image and copied the System Folder to an empty volume on my sawtooth. It didn't like the ROM that came with the Powerbook, so I experimented with some roms from the iMac lab at school. I ended up using Mac OS ROM 2.3.1. I used the "move the Finder? (or the System?) file out of the System Folder and back" trick to bless it. It worked like a charm. DON'T stick it on the same partition as Mac OS X. I recall at the time it did funny things to my 8.6 install, but it's been a while, can't remember what exactly. But if it's on it's own partition, it's very snappy.

ROM 2.5.1 + Mac OS 8.6 definetivly works! I´m using it right now

I own a Sawtooth but like almeath I don't have the original 8.6 install CD.

Could someone who has the Mac OS ROM 2.5.1 file please make it available for download so that other Sawtooth owners can try to install 8.6.

Thanks in advance.

No luck for me yet, with ROM 2.5.1. My machine (ID 406) doesn't want to work with a September 1999 G4 boot CD. It also doesn't want to work with a retail OS 8.6 install with ROM 2.5.1 dropped into the Sytem folder.

I think my problem is either:

(1) The CD I have was designed to only boot a PCI graphics G4.

(2) The firmware and/or boot ROM have been modified at some point, rendering the machine incompatible with Mac OS 8.6

I haven't given up yet though.

BTW, if anyone needs ROM 2.5.1, just PM me and I will give you the download link.

If anyone has a G4 boot CD which is confirmed to work with a 400mhz using AGP graphics (ID 406) machine, please let me know because I want a copy of your System folder! [] ]'>

I have done a lot of googling and have discovered the following:

If you have upgraded the sawtooth firmware (aka boot rom) using the 4.x update, the ability to boot into 8.6 is disabled.

This brings up the question of what sawtooth firmware versions support 8.6 booting. According to a Japanese site I found, the original 8.6 sawtooth shipped with firmware version 1.2f1. The first OS9 sawtooth shipped with 1.3f1. Later sawtooths shipped with 9.0.2 or 9.0.4 and there was a big jump in the firmware version to $0003.22f1, $0003.24f1, and $0003.26f1 (as reported by Apple System Profiler). The Japanese site seems to imply that firmware versions 1.2f1 to $0003.24f1 support 8.6 booting. Most people refer to $0003.24f1 as firmware version 3.2.4 which I believe is correct. However, here is where it gets confusing. The first firmware update for the sawtooth that apple made publicly available was firmware update v2.4. The Japanese site seems to imply that if you try to run this update on a sawtooth with firmware $0003.26f1 (v3.2.6) you will get a message saying the 2.4 update is not needed since there is a newer version. This leads me to believe that the 2.4 update is probably the same as $0003.24f1. In any event, I can definitely confirm that the v2.4 firmware update still allows 8.6 booting. In another discussion, I found a sawtooth owner who did in fact apply the 2.4 update who states he now had the ability to boot into 8.6, 9.0 and OSX.

The next question is whether you can restore 8.6 booting if you have in fact upgraded your firmware to v4.x. I can think of two possible solutions:

1. Perhaps it would be possible to write an Open Firmware patch/hack that somehow overrules the apple firmware and restores 8.6 bootability. In my google searches I can find no evidence that anyone has tried this so I dont know if is possible. In any event, it would require someone with lots of knowledge about hacking Open Firmware and there appears to be very few of those persons around.

2. The second and more likely solution is to reflash the sawtooth firmware to revert back to an earlier version that does support 8.6 booting. Of course in order to do this we would need some type of utility that would save a copy of the needed older 8.6 boot rom as well have the ability to flash the boot rom chip. My google searches do confirm that such utilities do exist but they may be hard to obtain. Here is what I have found out about these flashing utilities:

It appears that Apple had such a utility. I found a Pismo user who had a corrupt boot rom. He stated a friend gave him a Apple service CD that had what he called a boot rom reader/updater. This utility allowed him to save a copy of the boot rom from a good pismo and then using that saved copy reflash the bad pismo. In the end, he wasn't able to do it because the service cd had a 9.0 system folder that wouldn't boot on his pismo. It would be great if we could get this utility. Perhaps if members of this forum who have old apple service CDs could dig them out and see if they can find what this guy is talking about. The strange thing is, I am somewhat familiar with Apple service CDs from this era, the MacTest Pro CDs, and I don't recall these CDs ever having such a utility so I don't know what Apple diagnostic CD this pismo owner is referring to.

However, I have discovered other similiar utilities that may be easier to obtain. It appears that most of the cpu upgrade companies have these flashing utilities that they appear to be willing to make available to customers. For example, in a discussion on the apple support forums I found a Sawtooth owner who had a corrupt boot rom who wanted to reflash it with a fresh copy of the firmware. He stated that Sonnet sent him a utility he called the G4 ROM Utility that had the ability to both save a copy of the boot rom and reflash it. Of course, this guy was sort of in a catch 22 situation. He had the utility to reflash his sawtooth but he didn't have a copy of the boot rom. Since we have already seen at least one 68kmla member who is still running 8.6 on a sawtooth, if we could ever get a flashing utility, we could get that member to use it to save a copy of his 8.6 bootable firmware which we could then use to reflash other Sawtooths. (As an aside, there are several utilities that are available for saving copies of the boot rom of macs mainly for use among mac emulator users such as sheepshaver and basilisk. Some of the ones I know about are AutoCopyROM, CopyROM, and GetROM. There may be a few others. To the best of my knowledge none of the rom savers support flashing. In theory, we could also use one of these rom savers to get a copy of the Sawtooth 8.6 compatible boot rom. However, I dont know if the resulting saved rom file would be compatible with a firmware flashing utility).

I have also seen evidence that the other cpu upgrade companies may have had similiar flashing utilities. For example, on the Daystar/XLR8 support forum, a user wanted to reflash his firmware to remove the special patches the cpu upgrade applied to his firmware. Daystar responds by saying he should email support and request a firmware remover. They say it is a manual tool that allows you to reflash the original apple firmware. Though they don't say if it also allows you to save a copy of the firmware, I wouldn't be surprised if it does. Powerlogix also had a tool that allowed you to save a copy of the boot rom and then reflash it. In fact they made this tool publicly available. It was intended for use on only the PowerBook G3s and iMacs with their BlueChip upgrade for those macs. On those macs, the boot rom chip is located on the oem cpu card which is removed when you install the cpu upgrade. Therefore, before installing the BlueChip upgrade you had to use the flash utility to save a copy of the original firmware. Then after installing the BlueChip upgrade, you had to use the flash utility to write the firmware to the boot rom chip on the upgrade card. You can still download this flash utility from the Japanese Powerlogix site. The only issue with this is whether you can run the flasher on other macs. If not, can it be hacked to allow it to run on other macs.

Lastly, even if we can't get a copy of any of these flashing utilities, there may still be one possibility to reflash the firmware. Over on the cubeowner forum, a user named Pareis has discovered a way to use Apple's own publicly available firmware flashers to reflash the firmware to an older version. Here is a quick summary of what Pareis discovered:

As anyone who has used Apple's G4 firmware updates knows, they require you to boot into OS9 in order to use them. This presents problems for users who only have OSX installed and no longer have copies of a OS9 system folder. Pareis wanted to find out if there was a way to install the firmware update without booting into OS9. He did. He discovered that the firmware flasher itself runs under Open Firmware and that you could bypass the OS9 installer application. All the OS9 installer application does is to check to make sure you are running the right mac and whether the firmware version is newer. Pareis discovered that you can bypass this OS9 installer app by copying the included firmware file to the hard drive (or even burn the firmware file to a blank CD) and then boot into Open Firmware and choose the firmware file as the boot device which results in the flasher running and updating the firmware. He even wrote an OSX script to help automate this procedure. This led another user to ask since the firmware version check is bypassed whether it would be possible to run an older firmware update to in essence revert back to an earlier version of firmware. Pareis discovered you can. In fact, on his sawtooth he was able to successfully downgrade the firmware from 4.2.8 to the older 4.1.8 and then back to 4.2.8 again. This makes me wonder whether the same thing is possible using the older 2.4 firmware update that we know supports 8.6 booting. That is, try to boot into Open Firmware using the 2.4 firmware file as the boot device to see if we could bypass any version checks to revert back to this older firmware. However, Pareis hints that this may not be possible. His further analysis of the code in the firmware file shows that it will only flash a firmware with the same major version as in the ROM (That is, you can reflash from say 4.2.8 to 4.1.8 but you can't flash from 4.x down to 3.x or lower. However, you can upgrade from 3.x or lower to 4.x). He does not state whether it is possible to hack the firmware file to bypass this version check. This leads me to believe that it may not be possible to use this technique to try to downgrade the ROM from 4.x to 2.4. However, it may be still worth a try just in case Pareis is wrong.

As an aside, this guy named Pareis seems to be one of the few people I can find who seems to be a somewhat of an expert in using Open Firmware. It would be interesting to try to contact him about the problem of Apple removing the ability to boot into 8.6 to see if he could come up with some type of simple Open Firmware hack that would restore 8.6 bootability.

That is all I know about and more than anyone would probably want to know about Sawtooth firmware versions and the ability to boot 8.6

One other thing that has occurred to me that is completely unrelated to the topic of the correct firmware required for booting into 8.6 is whether any additional 8.6 system files were updated on the Sawtooth 8.6 Install CD.

Up to this point, it has been assumed that the key missing file is the Mac OS ROM 2.5.1 file and that all you need to do is copy this file over to a retail 8.6 install in order to boot a Sawtooth. However, even if you have the correct 8.6 firmware and the Mac OS ROM 2.5.1 file, there is still the possibility that other Sawtooth system files were updated and that those updated files are essential to the stable operation of an 8.6 Sawtooth.

It would be nice if someone with a Sawtooth running 8.6 could provide us with a listing of all the system files (control panels, extensions, etc) along with their version numbers so that a comparison to the retail version of 8.6 can be made to see exactly what was updated if anything on the version of 8.6 that came with a Sawtooth.

Having said all that, I doubt if much of anything was probably updated other than the Mac OS ROM file and you can probably safely drop the Mac OS ROM 2.5.1 file into a copy of the system folder from a retail 8.6 install and safely boot a Sawtooth.

Of course, a better solution would be a source for copies of the extremely rare Sawtooth 8.6 Install CD or absent that, a copy of the entire 8.6 system folder from a Sawtooth.

All but the ROM and the internal ethernet work just from a retail 8.6 CD.

Thank you ccmac for your extremely detailed responses. I was tempted to put this one into the "too hard" basket, but this has roused my curiosity now. I'm going to keep at this for the challenge...

It looks like I have ROM 3.3.4. If the 2.4 ROM update does correspond to 3.2.4 as you've suggested, then there is a chance that I can get this to work by applying it in openfirmware.

I do have a copy of 8.6 for a G4, so I'll look into making that available for those that need it...

According to the Japanese site that lists the various Sawtooth boot rom versions, $0003.31f1 (v3.3.1) appeared on the Power Mac G4 Gigabit Ethernet model. Technically, I would consider this a separate model but this site listed it as a Sawtooth variation. Given that almeath's Sawtooth has boot rom v3.3.4, it looks like some of the last Sawtooth's must have shipped with the same boot rom as used on the later Gigabit Ethernet models. Also, since almeath can't boot into 8.6 with boot rom v3.3.4, it looks like we now know that boot rom v3.3.x as well as the later boot rom 4.x updates removed the ability to boot into 8.6.