Hi all, I have an external hard drive, which I am wanting to partition and make bootable. This is partly for an emergency/troubleshooting scenario and partly just for the sake of doing it and learning. I have three partitions, one for time machine backups, one for a very basic snow leopard os and one for the mac os install disk (snow leopard also). Everything is going fine, installed fine, bootable etc, but I have just had a brainwave... I recall that the mac os install disk that came with my macbook (and is what I used for the image on the external drive and installing the os on the other partition) are made specifically for my model of macbook. 1- Does this mean that the partitions on the external drive of the install disk and/or snow leopard os will not work on another model mac than mine? 2- If they won't work, will they not mount at all, or will they just not be bootable? 3- Will any problems be fixed if I buy the retail snow leopard install dvd? 4- What is the difference in the installation of the install disc that came with my macbook and the retail install disc? Cheers.