I have an AMD opteron 170 with the asus A8n32 deluxe SLI. Im gonna reformat my whimpy 80gb HD and I need a new OS for it. I heard I can get the full version somewhere for around 100 bucks, but i dunno what that SP1/SP2 stuff means, or which one to get cuz there are versions out there from 100-200 $ and they all read to be the same thing. I just want the full basic Home xp edition with updates and all, cuz im starting from scratch. Some1 give me some advice please. Plus I have an e-machines xp home key, can i get a copy from a friend and use that to save some money?