I got a compaq presario which I am gutting and using some of the pieces on ym new computer build. Specifically, it has 2 hard drives that I am going to use for my new comp. My new stuff is: AMD 64 3000 (venice) ati radeon x800xl, MSI K8n ne04 mobo, 2X512 PC4000 Corsair value ram and im going to use my cd/rw drive and my dvd/rw drive from the compaq. My question is, when I use my 2 hard drives, a 40 gig and an 80 gig from the compaq, will I be able to use the win xp already installed that came with the compaq or am I gonna have to buy my own xp disk? This is important that I know, cause XP is a hundred buck s and I could use that $100 for something else. Oh yeah, and I am buying a Antec case with a 350 watt psu. THanks for the help