I mean, hey, since we're casting pennies into the wishing well, it would be awful nice if there were even rudimentary hardware accelerated drivers for a PCI GeForce 6200 for OS 9. It's the earliest and crummiest GPU with CoreImage support for dual-booting heathens.

Hi, what are you asking for it? Might be fun to try and make it go in my Molar.

(Yes I'm new here but you can validate I'm me from the other usual suspects of Mac Forums)

I am not sure why it isnt booting unless it needs to be the only OS on the drive.

The system folder has the system folder icon so I assume it has been correctly 'blessed', and it is recognised as bootable on the boot option screen

The disk initializer does see the HDD as an ATA device when I boot from CD but doesnt see any partitions and doesnt mount any of them on the desktop either.

They all appear fine in system 9.2.2 and OSX

Well you made the right call going to HFS since HFS+ was only introduced with Mac OS 8.1. Also, be sure your HFS partition is bootable and less than 4 GB.

Just supposition on my part - relatively new to old macs.
Using a PPC mac mini G4 1.25GHz and yes, formatted with APM not GPT
OSX and OS9 partitions in HFS+ and the partition I was trying to get system 7 to run on formatted in HFS+ initially, but when that didnt work, tried HFS

I should say it boots fine from the CD but the disk initializer shows the hard drive as empty and ready to initialize so I assume system 7 cant cope with the more modern partition table?
Guess I'd have to wipe my whole drive to install and it would have to exist on it's own?

I had formatted the spare partition (800mb) to HFS not HFS+ using the terminal in OSX

What do you mean "more modern partition" table? Your disk is formatted with Apple Partition Map, not GPT, correct? GPT is supported on Intel Macs and maybe Power PC Macs after July 2005. I don't have firmware dumps between April and June 2005 to check those. If you have a Mac or firmware version not listed in the "List of Open Firmware versions" at
 https://forums.macrumors.com/threads/question-how-powerful-of-a-graphics-card-will-work-in-a-beige-power-macintosh-g3.2303689/
then I would like a firmware dump to compare.

I should say it boots fine from the CD but the disk initializer shows the hard drive as empty and ready to initialize so I assume system 7 cant cope with the more modern partition table?
Guess I'd have to wipe my whole drive to install and it would have to exist on it's own?

I had formatted the spare partition (800mb) to HFS not HFS+ using the terminal in OSX

I've updated the Mac mini 7.6.1 CD to Test Version 0.2.

You can download the iso from the Macintosh Garden if you want to try it out:
https://macintoshgarden.org/apps/mac-mini-g4-system-7

CD 0.1 had some incorrect icons; the System itself is unchanged from 0.1.
Also now just a 43 MB download.

I tried installing on my mac mini on a partition - have OS9 and OSX already and used the Apple System Restore on the cd in mac os 9 to install on to a spare partition.
OS7.6.1 is seen on the boot menu (when hold down option key at startup) but trying to boot just gives the floppy icon with a "?"

Unfortunately didn't work in my testing and lacks most of the features of Sector like editing existing disk images.

Edit: upon further research, I see there isn't an easy way to do this after OSX 10.4.11 (the capability to initialize HFS volumes was removed).

There is always a HFS Disk Maker utility by the author of Pacifist. 10.9 and up.
Available here:
https://www.emaculation.com/forum/viewtopic.php?t=8337
And it's free