Key, yes, media, yes, but it could be part of a "restore" disk in which case it's tied to the system it's designed for. It looks at key fetures of the system, like motherboard make and model (through the BIOS), hard drive type, etc... Won't install unless certain key requisites are met. This is how Compaq, HP, Dell and rest do it. If it's an OEM copy, you'll get a disk, a really lame ass and very uninformative crappy ass 10 page booklet, and the key will be stuck to the side of the case, that is, if the company it was purchased from installs the copy according to the licence aggreement. If I am correct, you can still purchase a motherboard or hard drive and get an OEM copy of an OS as per the licence agreement.