OK so the school did allow me to use computers to make the drive, APM and everything, and *still* no luck. I managed to get it into verbose mode, here's the screen:The G3 can't boot from Leopard, but may start to boot. It's likely just another difference with the boot rom on older Macs, compared to (slightly) newer Macs. I'm not sure if the firmware will show the "prohibited sign" icon, or it just shows a kernel panic, or maybe just stops booting, and does nothing visible. I don't have one now to see what response it would normally show.
The 16GB sticks shouldn't make any difference, but 8GB is a better 'fit'. Any OS X will fit within 8GB (so far)
I THINK you could use the G3 iBook to make the flash drive installer, but I never tried building a Leopard installer, using a G3 running Jaguar. As you say, it will take quite a long time to do it with USB 1.1, but if all else fails, it would be worth the try, I suppose.

Have I not correctly used open firmware or something?
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OK so the school did allow me to use computers to make the drive, APM and everything, and *still* no luck. I managed to get it into verbose mode, here's the screen:The G3 can't boot from Leopard, but may start to boot. It's likely just another difference with the boot rom on older Macs, compared to (slightly) newer Macs. I'm not sure if the firmware will show the "prohibited sign" icon, or it just shows a kernel panic, or maybe just stops booting, and does nothing visible. I don't have one now to see what response it would normally show.
The 16GB sticks shouldn't make any difference, but 8GB is a better 'fit'. Any OS X will fit within 8GB (so far)
I THINK you could use the G3 iBook to make the flash drive installer, but I never tried building a Leopard installer, using a G3 running Jaguar. As you say, it will take quite a long time to do it with USB 1.1, but if all else fails, it would be worth the try, I suppose.

Have I not correctly used open firmware or something?