Installing Leopard without losing files with a portable drive

[spin360]

So my friend has Tiger and would like to install Leopard, and I remember reading somewhere that you could install it without losing any of your files? Is that true and how do I go about doing that?

I know you can install Leopard with an external hard drive, but my external is a bit different in that it is a portable drive. It has no external power source but simply powered by the USB. Will that still work? I guess it's almost like a giant flash drive.

 

[torchwood04]

You can either use archive and install or an upgrade install...

 

[torchwood04]

Oh, you can't install Leopard on a USB drive as of yet, you can on a Firewire however...

 

[Consultant]

Oh, you can't install Leopard on a USB drive as of yet, you can on a Firewire however...

On Intel Macs, OSX can be installed on firewire and usb drive
On PPC Macs, OSX can be installed on firewire drive