Hello, the thing is that I have two cpu, one that works wonderfully and runs win 7 64x, and another older one running win xp. The old one is half broken, but I can still start it up, so I know the hard drive is in great condition. What I'd like to do is to put the Xp drive into my already working Win 7 cpu, and then be able to dual boot it. I still got my XP installation cd, but i can't find the cd key. I checked the web around and only found people wanting to install xp on an empty drive. Thanks for any help, or tips on how to do it.