I know that there are plenty of threads here that instruct me on how to do this but I have seen those threads and they jump around in a random order. Also its seems that those threads don't clarify what I exactly want to do here. I have a copy of 10.5 in both .cdr and .dmg files in an external harddrive and I would like to install either one of those into my PowerBook which is currently running 10.4 Now its seems that it is only possible to do this by making a partition either in the external drive or on the laptop. I really dont want to make a partition but instead to just replace/upgrade the laptop from 10.4 to 10.5 I really hope that I dont need the retail disc to do so. If there is someone out there that knows how to do this please comment or leave a response. I would really appreciate your time and effort for helping out a stressed college student. :EDIT: This is not a torrent Leopard file but a backup i have made from the stone age of 10.5 and my retail dvd disc is long gone There is no time for apostrophes.