Installing OS 9 on G3 iMac 500

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Last seen: 8 years 1 month ago
Joined: Jun 10 2010 - 14:16
Installing OS 9 on G3 iMac 500

Hi all,

I'm sure that somebody here can help, though I'm presently ripping hair out.
I've a G3 iMac 500MHz, 256MB RAM, 20GB HDD. I'm trying to get OS 9 installed on it, and no matter how I try, I cannot get the thing to boot to any of my OS 9 disks. If I boot hitting the Alt key, I have no options that include the OS 9 CD. I've tried booting into target disk mode, and installing to the Mounted HDD from my iBook G4 (Making sure to install the OS 9 Hard Disk Driver), but it didn't work. I can get the Mac to boot to a Tiger CD, but of 3 OS 9 CDs (9.0.4, and two 9.2.1 disks) the Mac simply doesn't recognise them.

Has anybody any ideas as to why I'm coming up against this problem?

Cheers in advance,

gsmcten's picture
Last seen: 1 week 5 days ago
Joined: Oct 4 2005 - 18:52
I was just reading.....


I was just reading about these up at

Now, I am far from a regular Mac guy, but from what I was reading the highest OS this thing will see is 9.0.1.

Have you thought about starting with OS 8 and upgrading to 9?

I may be mistaken and you can check out the site for yourself

Good Luck,

Steven Smile

eeun's picture
Last seen: 4 days 5 hours ago
Joined: Dec 19 2003 - 17:34
If I may politely offer a reb

If I may politely offer a rebuttal, it'll run 9.2.2 no problem.

Are any of your install CDs the retail version of OS 9? OS 9 install discs were machine specific, and it was very rare for an install disc that shipped with a Mac to install on any other product.
Also, are your CDs burned versus your OS X install disc? The iMac drives could be picky.

The non-retail CDs should at least tell you they won't work with your system. If you're just getting the flashing folder with question mark, then I'd suspect a problem with the drive or the media.

"And one more thing..."
Just mentioned on another thread, your system partition needs to be less than 8 GB.

cwsmith's picture
Last seen: 6 months 4 weeks ago
Joined: Oct 13 2005 - 08:23

• Did you try booting while holding the "C" key to boot to CD?

• The iMac G3/500 (slot loader) does not have the 8GB system partition limit, but does have the 127GB partition limit. In either case, this would not prevent you from booting to CD.

• I will repeat the point about some of the G3 iMacs not liking burned discs, but that tends to indicate a failing optical drive, rather than any limitation of the logic board. Some G3 iMacs (tray- and slot-loading) read burned discs just fine, some don't.

• I will echo the point about machine-specific installers: they won't work on any other machine besides the one they shipped with. Is this a grey disc (system-specific restore disc), or a white disc with a big orange "9" on it (retail install disc)?

Last seen: 8 years 1 month ago
Joined: Jun 10 2010 - 14:16
In answer to a variety of tho

In answer to a variety of those questions:

I boot holding down C (or T, if I'm trying to install via Target Disk Mode). I have a selection of CDs, I generally make copies of my originals so as I can keep them from scratches and such, though I've tried my originals, copies, and installing via Mounted Disk image in Target Disk Mode - All to no avail. I do have an iMac specific OS 9.0.4 CD, which the Mac is unable to boot to. I know that the CDROM is able to use my burnt disks, because it boots perfectly to my Ubuntu and Xubuntu PPC CDs, and to my copy of 10.4 Retail. I am aware of the 127GB Partition limit, and I'm currently trying to install to a just-erased 20GB HDD - and the HDD has been tested working.

So, any more suggestions? I even tried installing Tiger, so I could set the startup disk to the OS 9 CDs - No change, it wouldn't allow the CDs to be selected at all.

Please help, before I lose all my hair!

cwsmith's picture
Last seen: 6 months 4 weeks ago
Joined: Oct 13 2005 - 08:23

Checkiing MacTracker and found a bit more info ...

• The early 500MHz models (summer 2000) shipped with Mac OS 9.0.4

• The later 500MHz models (early 2001) shipped with Mac OS 9.1

As I'm sure you've experienced, Macs normally can't boot to an earlier operating system than shipped with the machine (Mac OS 9.2.2 being an exception on those machines built before March 2003 that shipped with Mac OS X).

Is it possible you're trying to install 9.0.4 for a machine that's looking for 9.1 or higher?

After you've installed any version of 9, you'll have to use Software Update to bring the machine up to 9.2.2. Why not just get a 9.2.2 retail (or compatible OEM) installer CD and be done with it? $29 plus shipping

Dr. Webster's picture
Last seen: 20 hours 5 min ago
Joined: Dec 19 2003 - 17:34
I seem to recall OS 9 on thos

I seem to recall OS 9 on those iMacs being somewhat picky about RAM modules, but OS X was not. Have you tried swapping out the RAM?

Last seen: 8 years 1 month ago
Joined: Jun 10 2010 - 14:16
Well yes, I could just buy a

Well yes, I could just buy a disk, but since I've already got disks, I just thought that there may be some way of forcing it on.

Also, yeah, I had to swap around my RAM, as when I powered it up again for the first time in a few years I had a 'No Good Banks' beep code. I suppose I could try some old 64MB modules, just to check. Cheers for the idea.

Hawaii Cruiser's picture
Last seen: 1 year 4 months ago
Joined: Jan 20 2005 - 16:03
Just copy it

There is a very simple solution. Unlike OS X, OS 9 does not have to be cloned to make a copy. You can simply drag and drop a copy of 9 to another hard drive and it will boot and work fine. Sometimes the copied system folder needs to be re-blessed, but I've encountered that only rarely. You could try copying--while in target disk--an OS 9 that's been installed on your iBook or other Mac. The best thing would be an OS 9 installed from a retail installation disc.

I keep a burned copy of an installed OS 9 on CD. Even with many third party applications, it's still less than 500mb. Among the apps installed, my burned copy has DiskWarrior, Techtool, and Norton Utilities (with Filesaver emasculated), so I can use the CD to fix most OS 9 problems. DiskWarrior will bless systems. The old OS 9 versions of those software can be found on eBay these days for pennies. I haven't bothered to install OS 9 in ten years maybe. I just copy from the CD OS 9 I made. It's actually OS 9.2.2, so it's all updated, and I've installed it (copied it) to many many CRT iMacs and it has worked on all of them, from the 233mhz to the 600mhz (never had a 700mhz, but I'm hoping for the day--a graphite would be a keeper). There have been some iMacs that have had a hard time reading burned CD's, but like mentioned above, that happens with drives that are wearing out. 233mhz Rev. A drives in good condition will read burned CD's, and all the others will also.

dankephoto's picture
Last seen: 10 months 1 week ago
Joined: Dec 20 2003 - 10:38
well, now . . .

I've got no solution, but I have a sort of relevant tale. My daughter's SL iMac used to hum along on OS9 quite happily, until I installed X. From then on I could not boot to any classic MOS, even the previously installed 9.2.2 system folder won't boot it, no matter the HDD used, or from a CD or FW drive or anything.

So fooey.

dan k

Last seen: 6 years 6 months ago
Joined: Aug 22 2010 - 18:57
I've been able to use the 9.2

I've been able to use the 9.2.2 installer CD from an iBook 600 (Rage 128) on both a G4/450 and a Summer '01 iMac 500 without fault.

I've found that a model-specific disc works fine with models produced before when the disc was pressed without fault. A System 7.6.1 CD that came with my old Powerbook worked on a 6100. An 8.1 CD that came with a bondi iMac worked on the Powerbook and the 6100.

The only caveat I've found is that not a single disc I have will boot on a 5200. Considering it's a 5200, I ended up giving it to Goodwill. Blum 3

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