Desperately Seeking Mac OS 9.1

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Joined: Jan 23 2005
Posts: 595

I'm having an incredible amount of difficulty installing Mac OS 9.1 on a PowerMac 9500.

Here's the configuration:

2GB SCSI Hard Drive
Mach 64 video card

Here's what I'm trying to do:

Install Mac OS 9.1 on the hard drive. I'm using the complete Mac OS 9.1 install disk i.e. install 9.1, not 9.0 with 9.1 update.

Here's the result:

Mac OS completes the installation without problems. However, when I reboot in Mac OS 9.1, I get the following:


BOMB! Sorry, a system error has occurred.

Address error
To temporarily turn off extensions, restart and hold down the shift key.


If I reboot with extensions off, the system appears to boot fine and the desktop appears on screen. I've tried disabling various extensions and control panels, to no avail.

Help... Please...

I have no idea what the problem is here. Have any ideas?

Any help, as always, would be greatly appreciated.

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Joined: Jan 23 2005
Posts: 595
Ooops, I Forgot To Mention...

I forgot to mention that there are no third party control panels or extensions installed on this machine. Just the stuff that is installed with the recommended Apple installation.

Any help, desperately needed...


davintosh's picture
Joined: Dec 20 2003
Posts: 554
USB Components

Try disabling any extensions related to USB expansion cards. I've had trouble getting 9.anything to run with USB on beige machines -- always locks up on startup -- and disabling those extensions gets them working. Hopefully you don't need the USB, cuz it's a bear to get it working.


Obsolescence is just a lack of imagination.
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sourapple's picture
Joined: May 27 2004
Posts: 209
this is probably illegal, but

Deleted - Tom


token's picture
Joined: Dec 20 2003
Posts: 231
Burning a copy of a proprieta

Burning a copy of a proprietary operating system is *probably* illegal? piracy on Applefritter.


The 'fritter critter formerly known as guskid.

Joined: Jan 23 2005
Posts: 595
That's okay...

Actually, I already have Mac OS 9.1. I'm just having trouble installing it on a PowerMac 9500. I have installed it on a 7300/200 without problem. I have installed it on a beige G3/233 without problem as well.

For some peculiar reason, Mac OS 9.1 will not boot on my PM 9500/150. I get one of two types of error on startup. I will either get an address error or a bus error. If I boot with extensions off, it boots fine.

I have tried disabling all of the USB related extensions, as suggested, to no avail. I have tried disabling all of the firewire extensions, again, to no avail. I have tried disabling just about everything... but it's a "no go."

I'm really perplexed. It's a 150MHz 604 processor, so there shouldn't be a problem. I have 80MB's of RAM, which should be plenty, given that the 7300, which runs 9.1 flawlessly, has only 64MB's of RAM. I'm installing to a 2GB SCSI hard drive, so there's plenty of room for the installation.

I can install Mac OS 8.6 on the 9500 with absolutely no problems at all. Why the heck won't 9.1 work? I'm pulling my hair out here. Going grey before my time... losing touch with reality... What gives?

I've decided that I'm eventually going to install System 7.5.5, do a Linux install on the 9500, and use it as a Linux server. However, I'm the kind of guy that just can't move on until I solve the mystery: Why won't Mac OS 9.1 boot on my PowerMac 9500?

Macinjosh's picture
Joined: Feb 12 2004
Posts: 216
A Few Guesses Re: Bombs

Just a few guesses off the top of my head since I know how it is to want to solve one of those mysteries. As a preface, i dont have the string o' messages at hand as I write this, but hey, if I mention something you've already done, it's still worth mentioning, right?

1) RAM flakiness or in need of a reseat - I'd crack 'er open and reseat RAM, proc probably not needed but wouldn't hurt. While youre there, drive cables and whatnot probably wouldnt be a bad idea either, ditto for cache sticks, cards, etc.

2) Good CUDA/reset button push.

3) If you're like me, you've probably got an extra CD-ROM drive lying about (sounds like you've got a machine with one.) This is where I start going out into Rare Possibilities, but I'd try that same CD with a different drive, preferrably the one that already worked. Wink

4) Barring all of that, it sounds like the system is pretty darned stock, but I'd start pulling anything extraneous, perhaps swapping RAM around/in/out, and go at it as pristine as possible.

Addendum- Somewhere in there, I'd run that CD through Disk First Aid or similar, just to be sure, and maybe give it a good cleaning. What one CD-ROM drive can get around just fine, another may throw corruption/worse at you for.

YMMV; just throwing the standard stuff out there.

-- Macinjosh

sourapple's picture
Joined: May 27 2004
Posts: 209
Re: Burning a copy of a proprieta



Joined: Jan 28 2004
Posts: 82
Yeah..if you talk about illeg

Yeah..if you talk about illegal stuff big dog apple will shut this little site down =/

Joined: Jan 23 2005
Posts: 595

Hmmm, I don't think it's the RAM cuz Mac OS 8.6 runs just fine. I was thinking that a hardware problem would cause any version of the OS to crash. Am I wrong to assume that? I would assume that the same logic would apply to such things as drive cables as well. My logic: If the drive cables are sufficient enough to allow the 9500 to boot 8.6, they should also be suitable enough to boot 9.1.

The cache? Now there's something that I'm not too sure about. I dunno too much about the 9500, but I can't find any documentation on an L2 cache for this machine. Is the L2 on the processor card?

Looking at the 9500 service manual, I can see that there is a ROM slot among the DIMM slots. The ROM slot on my 9500 is empty. Should there be something in there? Could the absence of a ROM SIMM in the ROM slot be contributing to the problem?

The CUDA reset... I've done that a couple of times and it doesn't seem to make any difference.

I haven't tried suggestion three yet. I'll give that a try when I get a chance. Thanks.

Ahh... Suggestion four... I'm thinking that this might be a problem. I read the 9500 service manual and it says that the DIMMS should be installed in pairs to achieve a performance gain through memory interleaving. However, for interleaving to work, the DIMM's must be installed in pairs *and* be of the same size and speed.

The service manual says that DIMM's should be installed first in slot A6 then B6, followed by A5 and B5, A4 and B4, etc. So, my question is this: If the DIMM's are not of the same size and speed, and there's no possiblity of interleaving, is it still necessary to install the DIMM's in the A6,B6,A5,B5,A4,B4,etc., order?

By the way, what does YMMV mean?


dankephoto's picture
Joined: Dec 20 2003
Posts: 1900
Some questions and some things to try . . .

Here're some questions for you - when exactly does it bomb during boot? Be specific about what is happening at the moment of bomb. Have the extension icons begun their march across the screen, or is the bomb before that?

Which version of 9.1 do you have? Retail? Model specific? Got a part number or description on the CD?

Things to try, not necessarily in this order . . .

1) move the display card to different slot, preferably in a different bank (there are 2 banks of 3 slots.)

2) de-interleave ram, move to different slots

3) remove existing ram, replace with known good ram

4) move the Preferences folder to the desktop, reboot, allowing OS to build another Prefs folder

5) use Conflict Catcher to help isolate the problem extension (if any)

6) replace SCSI cables with known good cables

7) update HDD driver with latest version of Drive Setup that you have

8 ) 9500 has 2 SCSI buses, place HDD on the other bus

9) check SCSI bus termination, drive IDs

10) reset the PRAM 20 times in a row. Well, 20 is a bit over-the-top, but do it, say, 5 times.

11) install MacsBug (drop loose into System Folder), when bomb occurs, you'll drop into debugger, type "stdlog" and let it write out the crash log.

12) you have another PCI mac? Test CPU card in other Mac.

Answers to your questions:
The 9500's L2 cache is soldered to the logic board, can't be removed or upgraded.
That ROM slot you notice is unused, don't worry about it.
DIMMS can be installed anywhere, don't have to be in order.
YMMV = "Your Mileage May Vary".


dan k


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Joined: Jan 23 2005
Posts: 595
The details...

I have the retail version of OS 9.1. The error occurs just moments after the Mac OS 9.1 boot screen appears, just before the extensions start their march across the screen.

1) I haven't tried moving the video card to a different slot yet. However, I have tried putting the video card in a different Mac. I will put the video card back in the 9500 (in a different slot) in a different slot tomorrow.

Just out of curiousity, the 9500 has an ATI Mach64 video card, is this a better video card than the built-in video of the 7300 and beige G3/233?

2) The memory was already de-interleaved. I moved the DIMM's around today, and they are now interleaved. I will attempt an OS 9.1 install tomorrow and see if that makes a difference.

3) Swapped memory today, too. Pulled the DIMM's out of a 7300 and put them in the 9500, put the 9500's DIMM's in the 7300. I haven't yet attempted another 9.1 install on the 9500 (see note 2), the 7300 boots 9.1 just fine with the 9500's old DIMM's.

4) Haven't tried moving the preferences file. Actually, never even thought of it. I will try that tomorrow too.

5) I don't have Conflict Catcher. Is Conflict Catcher commercial software? If so, is there a demo/trial version available?

6) I haven't tried replacing the SCSI cables. When I installed OS 8.5 and the 8.6 udpate, the 9500 worked fine as configured. I really don't have an extra SCSI cable laying around at the moment, but I would have figured that SCSI related problems would be universal i.e not OS dependent.

7) The Mac OS 9.1 install updates the HD driver when it does the OS install. The Drive Setup software included with 9.1 is the newest version that I currently have.

Cool The SCSI cable is currently plugged into the SCSI bus that faces upward (when the logic board is attached and 9500 is in upright position). I looked at the logic board and saw the second SCSI bus slot (the one that faces the power supply) and it looks like it's gonna require some ingenuity to plug the SCSI cable in there. I'll give it a try. Curiously, do both SCSI buses operate at the same speed?

9) The 9500 has two hard drives: Startup disk: id=0 Second HD: id=1
CD ROM: id=3

10) I've probably reset the PRAM at least 500 times by now. I'll try five consecutive resets though.

11) I don't have MacsBug. Is MacsBug commercial software? If so, is there a demo/trial version available?

12) This is what I have been thinking about. I have looked very closely at the 9500 CPU card and there is a decal on the card that says, "use in 9500 only." I do not have another 9500 that I can try the CPU card in, but I do have a 7300 that I could drop the card in. Would this cause any problems?

I suppose there are two possibilities for swapping the CPU card. I could put the 7300's CPU card in the 9500 or I could put the 9500's CPU card in the 7300. Are these two CPU cards interchangeable? If so, any risks/benefits?

The 9500's CPU card clearly states that it is for the 9500 only. The 604e CPU card that is in the the 7300 has no such markings. Am I taking a risk by putting the 9500's CPU card in the 7300? Am I getting any benefit by putting the 7300's CPU card in the 9500 as opposed to leaving it in the 7300?

I must admit, I'm partial to the 9500's form factor. If I could have my 7300's CPU card in the 9500 without experiencing any performance deterioration, I'd much prefer the beefed up 9500 to the stock 7300.

Thanks for the suggestions/answers/help. Applefritter and its users are a great resource. I hope it's around for a long time to come.

Joined: Apr 22 2004
Posts: 379
To answer some questions...

1) The Mach64 chipset is the ancestor of the Rage line of chipsets. The Mach64 is slower than the built-in video on the Beige G3, and about the same speed or slightly faster than the built-in video on the 7300/7500 series.

12) The CPU daughtercards that came with the 9500 went up to a 604e/200 or a dual 604e/200. These are compatible with the 7500/7300/7600/8500/8600/9600 daughtercard slots.

The 9500 was a good machine with the exception of that @#$@#&*$@ed case. To add memory, remove the logic board. To change the battery, remove the motherboard. I like the 9600 MUCH better - same slots, much easier case to work with.

Joined: Jan 23 2005
Posts: 595
I wholeheartedly agree...

I wholeheartedly agree with you. The 9500 case is a bit of a bugger to work with but I prefer the tower form factor to the desktop form factor.

If I could put the 7300's CPU card in the 9500 and realize a performance gain (I haven't yet checked the bus spec's for the 9500 logic board versus the 7300 logic board) on the 9500, I would decommission my 7300 and shelve it for parts and/or future use. That way I could use the DIMM's from the 7300 in the 9500 to give the old 9500 a little more oomph...

Curiously, my 9500 has an internal CD ROM, and two SCSI hard drives. The SCSI cable and the drive power cable have one extra plug each... Where oh where would one mount that additional drive?

I'm finding the PowerMac 9500 to be very peculiar indeed (but I still love it.).

Jon's picture
Joined: Dec 20 2003
Posts: 2804
The 7300 has a 50MHz bus, and

The 7300 has a 50MHz bus, and the 9500 has a 40/50MHz bus that is set by the CPU card.


I am not in this world to live up to other people's expectations, nor do I feel that the world must live up to mine. - Fritz Perls

Joined: Apr 22 2004
Posts: 379
Extra connector

I've heard of a shelf that could be placed on the bottom of the 9500 case for extra drives, but I've never seen one.

I've got a stripped 9500/132 in my office that had similar problems to yours. I had enough Macs to just use another machine and not worry about it though. Smile

Joined: Jan 23 2005
Posts: 595
Me not worried...

I'm not altogether worried about the 9500; I picked it up for a measly $25. Although I do like the aesthetics of the 9500. There's just something about the look of the 9500 that I find very appealing.

I'm committed to getting the bugger to work the way I want, even if it means breaking out the old hammer, hacksaw, chisel, and oxy/acetylene... Come hell or high water, I'm gonna get this puppy producin'...

Where there's a will there's a way... At least, that's what my mommy used to tell me.

Thanks for everything guys...