LeopardAssist

LeopardAssist is a bootloader that allows Mac OS X 10.5 "Leopard" to be installed on an unsupported Mac model with at least a PowerPC G4 processor.

Description
Apple set the installer of Mac OS X 10.5 to require an 867 MHz PowerPC G4 or faster processor. LeopardAssist uses Open Firmware to identify the computer as meeting the minimum clock rate so that installation is allowed to commence, although the CPU may in reality be slower. LeopardAssist still requires the system to contain at least some type of G4 processor for installation.