go buy the retail dvd and you will see it will install without any problems but it will slow your ibook right down ,it does my 1.42 ghz mini with 1gb ram slows right down , feels more like my mini would have only a 450mhz G4 and 256mb ram when running leopard , i bought the disc out of curiosity because my mini is my operating system test platform so i needed leopard on it and because everyone was praising the leopard like it was one of the 7 wonders of the world , but i definitely keep tiger on the Mac's i have to do any kind of work on , as tiger is still the best operating system apple has developed in recent years