Hello all. I'm doing a new build and I want to know how to use my old hard drive, running windows xp pro, as the primary hard drive for my new computer. The reason I want to do this is to save $100 on a new os. windows has a tricky activation system to stop piracy so if I just install the hard drive without doing anything else I'm almost certain that it either wont work, or wont be a genuine activated copy of windows. Can someone please tell me how to solve this problem?