the lowest previously unsupported hardware

[teroyk]

It seems that all 90's PPC-macs support at least Mac OS 9.1.

But do I remember right that there was some software that helps install Mac OS 9.2.2 for those macs?

So what is the lowest previously unsupported hardware for Mac OS 9.2.2 with or without CPU upgrade?

[Mat]

Yes, you are remembering correctly. The program is called os9helper, and recently hosted by OWC: https://eshop.macsales.com/OSXCenter/OS9Helper/Framework.cfm?topic=32

As for your question about the MAcs which can use 9.2.2. with os9helper, see the compatibility matrix of the original producer os9forever.com: https://web.archive.org/web/20110927020920/http://www.os9forever.com/Compatibility.html

[teroyk]

As for your question about the MAcs which can use 9.2.2. with os9helper, see the compatibility matrix of the original producer os9forever.com: https://web.archive.org/web/20110927020920/http://www.os9forever.com/Compatibility.html

Whou! this add some non Apple machines to work with 9.2.2:
Umax J700   , Umax S900, Umax C500, Power Tower Pro, Power Center Pro, Power Base and Power Curve

But there might be more non Apple systems with acceleration cards that support at least Mac OS 9:
I found some information about XLR8 MACh Velocity acceleration card:
System Requirements: DayStar Genesis MP 720 or greater and Millennium
Software Requirements: with G4, Mac OS v8.6 or greater, Mac OS 9 highly recommended

[LarsG5]

Power Macintosh can boot into 9.2.2, just not with os9helper. You have to use MachID Wannabe and some other steps in between, but yeah, I use 9.2.2 on my 4400 and it works just fine.

[LarsG5]

Power Macintosh can boot into 9.2.2, just not with os9helper. You have to use MachID Wannabe and some other steps in between, but yeah, I use 9.2.2 on my 4400 and it works just fine.

I meant Power Macintosh 4400, sorry for the typo.