Hi all I want to upgrade the mac os on my girlfriends powerbook 1.67ghz 2gb ram from panther to leopard. I have a macbook pro which I bought when leopard came out last year, it has a tiger os disc and a leopard upgrade disc. I know my laptop has an intel chip and her's has an ibm G4 chip but are the OS discs multiplatform? Also if I use a disc thats already installed on a system will it disable that system when it connects to the internet? Do apple track that kind of thing?.