No idea what I'm doing....I've always been a PC guy and having never used a Mac, this is a bit strange. I got it from a closing CompUSA store that had it in their tech shop for Apple customer backups. It has Leopard, a 500GB drive, and 2GB of RAM (The drive and RAM were added by the store I guess seeing as how the paperwork says it came with a 160 drive and 512 RAM.) So now what? What's the best use of this beast? I've got a spare 8800GTS 640 sitting around, can I install it? Nvidia doesn't show any Mac drivers.