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Installing OS9 from USB on iMac

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Hiya there!


I'm wondering if anyone has any idea on how I could go about installing OS 9 on an old iMac G3 (the bubble one, I got the blue!) that I was given by a friend. I found that the HDD was dead, and there is no CD-Rom drive in the iMac, so I'm stuck with... nothing at all, I can't boot anything (I do get the flashing system folder/question mark icon, so I know the mac actually works) and I can't install anything.


I also have an old OS9 install CD that I found, and I'd love to be able to use it to install to the mac - unfortunatly, the only thing I can possibly boot from is a USB drive, which I happen to have (a 2 GB USB key to be precise).


Without necessarily booting the install itself on the USB key and installing from it like I would a CD-ROM, maybe I could use some sort of software (like SheepShaver?) to "install" OS9 on the key, boot from it, and then copy system files?


I'm not really knowledgeable of Macs beyond installing OSx86 on my PC, so this seems like a huge job to tackle from my perspective. Maybe someone that's grown up with Macs can throw me a bone here? I'll fetch... (bad mac joke).


Oh and another thing, if I plug in a "pc" usb keyboard on that thing, will I be able to use the windows keys as mac keys? XD




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You can probably buy a cheap cd-drive from eBay. Not really worth it to me. I don't think the iMacs boot up from usb, they only did it from firewire connection to another computer. They do not boot up from external usb drives.


If you can find drivers for the keyboard, it can probably be done through it. It can also be done using a hex editor, but it has been so long that I no longer remember how.

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Well I don't have another Mac... here's what I thought from gathering info from the net:


First off, the computer is actually an iMac G3, with the following specs:

Model number M5521

450MHz/512k L2/64MB



That is, what was originally in it. Right now there's no drive, HDD or DVD, and the memory is 512 MB (2 of 256 I got from old P3 computers). The USB device I have is actually an external IDE enclosure, so I have a 20 GB IDE drive in there which would work on the mac, if it had the system on it.


What I figured I could do:

Setting up through an emulator of some sorts, I could format the drive to HFS, install OS9 (I have 9.0 install CD and updates up to 9.2.2), then just pop the drive in the mac and voilà! The problem is, I can't seem to find an emulator that'll do the job. Sheepshaver can't mount actual drives under Windows, only drive "images". PearPC seems to only emulate OS X (maybe it does 10.0.1 , but I don't have CDs for it), and Basilisk can't support OS 9 or 10 at all, only older versions (which if I read correctly, aren't compatible with the G3 anyway).


Maybe there's a way to do it under OS X, if I just install 10.4.7 on my laptop again (removed it for lack of space), but only if I'm sure to get this under way...


Any ideas?

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It can't be that simple, unfortunately. I did try it just for the sake of argument, but no, I still get the flashing "No System" icon.


I would assume this could be caused by two reasons. Either the drive needs to be set as bootable (just like Windows partitions need to be set as active and the MBR needs to be properly formatted also), or the drive needs to be formated in HFS instead of HFS+ (I have no idea how to format a drive just in HFS instead of the default extended HFS OS X uses).


I didn't use a SIT file though, since the format sheepshaver uses is actually DMG, I just mounted it in OS X and copied the files inside of it. I assume this wouldn't make much of a difference?

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Ok so I used iPartition to format the drive with HFS (the true OS9 supported filesystem), and I could actually mount the drive properly under sheepshaver, to install it, and to boot it, all through the USB connection.


Unfortunately, when I put the hard drive physically in the computer... No go, it didn't boot up at all. Same flashing icon.



Since this is a 450mhz G3 processor, does it actually *require* a certain version of the OS? The one I have is 9.0 , maybe I'd have to upgrade to 9.2.2 before it'll work?


Or maybe I'm disillusioning myself and the mac is just broken :'(

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The problem is the lack of cd/dvd drive. Without it, its hard to tell. Is the HD set as master or slave? Try both ways. It may be that you need to rebless the System folder, but that can only be done by booting up from a cd/dvd.


With the os 9 hd inside the imac...

as the computer boots up press and leave pressed the "command" + "option" + "O" + "F" keys to boot up into the firmware screen

type "reset-nvram" and press return

type "set-defaults" and press return

type "reset-all" and press return

the computer will reboot


as it boots up again...

Press and hold the "command"+ "option" +"P" + "R" keys. Leave press until it boots up around 5 times.

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