Install Leopard on a G4 PowerPC

As the developers of LeopardAssist point out, when Apple released the final system requirements for Leopard, an official cutoff point of 867MHz was introduced, leaving several machines, even those just 67MHz below and with dual processors, out in the cold.

Leopard isn’t therefore supposed to run on G4 computers with less than 867MHz and if you’ve ever tried, you’ll know that the installation is simply aborted. LeopardAssist works around this problem by allowing you to install Leopard without modifying it or reducing its capabilities in any way.

When you run LeopardAssist, it virtually changes the CPU speed to 933MHz thus fooling Leopard into thinking that your system is fast enough for it. It works by writing a script into your PRAM so that when you next restart your Mac with the Leopard CD inserted, it will run the installer automatically from your CD/DVD drive. After installation, the Leopard installer will automatically restore the default boot drive and return your Mac to normal.

I’m always wary of using anything that modifies a Mac’s PRAM but for G4 owners, Leopard Assist may be the only option to install Leopard.

Fake CPU Speed lifted to 933MHz, giving the system room to “give or take” from the modified CPU speed.Disables “Restore System Defaults” if G5 or Intel detected.Changes to behavior on Multi-Processor SystemsAdded “Demonstration Mode” for unsupported systems to demo the software.Code Cleanup.Changes to Final Restart step, now shows steps to recover from problems.

Changes

• Fake CPU Speed lifted to 933MHz, giving the system room to “give or take” from the modified CPU speed.Disables “Restore System Defaults” if G5 or Intel detected.Changes to behavior on Multi-Processor SystemsAdded “Demonstration Mode” for unsupported systems to demo the software.Code Cleanup.Changes to Final Restart step, now shows steps to recover from problems.