Hello I am new to the site just logged in today! My question is I have a p4 Hp a450n if I reinstall windows xp does that reformat the hard drive like clear it all? Also do I have to buy new retail windows I do not have the cd but I have a cd key sticker thing on my computer. My computer is 3 years old and I am tired of paying geek squad... It has slowed down a lot so will this help it out? Sorry about the noobish questions... Thanks in advance!