Okay, newbie builder here. Just cannibalized my old computer and put some old components into a new case/mobo/processor. It's an Asus Z97A. I am running Windows 7, or the hard drive from the old machine I put in this one is running Windows 7. I can not get it to boot and I don't know how to make it. I feel like there is a super simple answer here and I just don't know what it is? What step am I missing to make the old HDD and Windows 7 work with the new MOBO without having to reinstall?