One of my Macs is a 2001 vintage G4 733 with a dual 1.8GHz G4 upgrade. This should fit well within Leopard’s minimum system requirements, but the CPU upgrade I’m using presented a complication. Without a kernel extension from Gigadesigns called ‘Giga-Meter’, MacOS recognizes the upgraded CPU’s as ‘PowerPC 60? 467MHz’ and therefore won’t update due to the new minimum requirement of 867MHz. This extension can’t be loaded from a DVD since you’re booted from the Leopard installation CD at the time you get denied. I resolved this by doing the following (this is for fairly advanced users):
- Click OK to the dialog informing you your Mac isn’t fast enough, NOT RESTART
- You’ll be presented with an idle desktop, and will be able to choose ‘Terminal’ from the Utilities menu.
- Run ‘
kextload /Volumes/Macintosh\ HD/System/Library/Extensions/Giga-Meter.kext’. This extension loads into the leopard kernel without difficulty.
- Quit Terminal, choose ‘System Profiler’ from the Utilities menu. It should now report your CPU at the proper speed.
- Relaunch the MacOS X Installer by choosing Terminal again from the Utilities menu and running the following:
/System/Installation/CDIS/Mac\ OS\ X\ Installer.app/Contents/MacOS/Mac\ OS\ X\ Installer /System/Installation/Packages/OSInstall.mpkg
(All on one line) Leopard install will proceed normally. Leopard also requires a CoreImage capable graphics card for a lot of its new stuff, so if people don’t have a Radeon 9600 Mac Edition in their upgraded G4’s, now’s the time to get one. This graphics card upgrade works fine under Leopard as well.