I bough a pc about a year ago from bestbuy and now I'm building my own pc. If I deactivate the product key (http://www.howtogeek.com/124286/how-to-uninstall-your-windows-product-key-before-you-sell-your-pc/) and use my old hdd from the pc I bought from bestbuy, and put it in my new pc, will I be able to use the copy of windows. Or if there is any easier way please tell me. Thanks