My PC is very slow, from booting to shutting off. So i decided to reinstall windows, and format my HDD. I lost my original Windows XP Home CD, so i downloaded a Windows XP Home Service Pack 3 iso, and burned it on a CD. I reinstalled windows, but windows won't accept my ORIGINAL Windows XP CD key. Now the question is, Could it be because the CD key wants a Windows XP Home Service pack 1/2? Or shouldn't that matter at all?