A serial ATA just laying around!?
I\'d load Windows on the biatch and make it my primary. I also have a P4PE, we have SATA ports, it\'s a lot smaller than the wide IDE cables but keep in mind
you need a different power connector for SATA drives. Check to see if your PSU has one. If not you can be a cheap adapter.

edit- just found the
P4PE has the ports as an option. If you have integrated LAN, you most likely have the ports as well.