Hi all (1st post here and kind of new to the Mac world), I have a Mac Pro with only a single 500GB hard drive on it which has OSX 10.5.4 installed. I use for music production using Pro Tools LE 7.4 with many other 3rd party plugins. I've used up about 100GB of space on my hard drive. My 2 questions are: 1) Can I partician off my current hard drive and then clone the 100GB onto the new partician? (so now I would have 2 hard drives with the same version of OSX on my computer) 2) When I shutdown & switch the computer back on, would the Mac recognize the clone as ''another OSX'' on my computer? and I can hold down option(alt) to select which one I want to boot from? I'm asking these 2 questions because I would like to upgrade my OSX (and everything else on it) but when I do, all my programs will become ''incompatible'' with the new OSX!, so this way I could go back in time, ''back to the way my computer used to be'' and run all my old programs as I used to if I needed something. Thanks everyone!