Hi Or if you have Tiger installed you can use LeopardAssist which gets round the installer and is very simple to use. I did it on my 400Mhz Sawtooth PowerMac G4. Simon --- http://www.simonroyal.co.uk - Mac news, reviews, guides, upgrades, hacks and more... - http://www.nmug.org.uk - webmaster for Norwich Mac User Group - The box said requires Windows XP or better, so I bought an Apple Mac. On Feb 10 2009, Dennis Fazio wrote: On Feb 8, 2009, at 2:22 PM, Mandm44 wrote: > i tried to install 10.5.6 into my PowerBook G4 running 10.4.11, and > it was no go...how did you make that work? Leopard will not install directly on a Titanium Powerbook less than 867Mhz. However, you CAN install it if you have access to any other Mac which will take a direct install of Leopard. You simpley connect the TiBook to the other Mac in firewire disk mode, load the install disk on the auxiliary Mac and specify the install go onto the TiBook disk. When you restart the TiBook, voila, OS X Leopard will boot and initialize. You can then migrate your home directory from a backup. I have Leopard running on a 667Mhz TiBook and used my Aluminum PowerBook to install it.