Turning Our Old Power Mac Into a Server

Jenn and I have an old Power Mac G5, which has fallen into disuse since Jenn acquired her newest MacBook Pro. We had the thought of turning it into a server for both our freelance businesses and our home media (music, movies, photos, etc.).

I wanted to see if anyone could offer suggestions on how we might best retrofit this as a server. Adding hard drive space comes to mind, followed by maxing out the memory. Anything else? Would we need to install a server version of the OS?

Note that it is PowerPC-based, not Intel. This means that we are limited on certain software — for example, we can’t run any version of Mac OS X above Leopard (10.5.x).