Hello, ive had this pc for around 3 months and its running Windows 10, im going to upgrade my motherboard and cpu (currently running amd 6800k), im upgrading to an Intel i5 4690k. The questions im asking is will i need to re-install windows(i dont have a disc to install it) and because i bought this pc from someone will i technically own this version if windows? I dont have a product key, what are the steps i would need to do to successfully carry this out?