Obviously not without some kind of converter as ones IDE and one is SATA , but if I had one is it possible? I ask because my G4 Dual 1.42 is on its knees at the moment with an audio project Im working on. After some impressive whining at my boyfriend hes volunteered his G5 dual 2Ghz for the task, but the thing is Ive got my Mac set up just the way I like it. I have one hardrive for my OS and everything else, and one for my audio library, so I need to be able to put both in his G5. In my head Id literally be getting my computer but faster, unless of course there are any quirks between Tiger when its installed on a G4 or G5? Id really appreciate some help! Thanks!