Even if you order the recovery disk from the manufacturer, it will most likely also be linked to the motherboard. You'll probably get an error if you try to use it in another computer. There is always a way around stuff if you're willing to spend the time researching it (and you're up to the challenge!)
I had an old HP Pavilion with Windows 98, and was able to hack the recovery disk using a brute force password cracker. Once I had the password for the disk, it was just a matter of copying the Windows files to a new disk.
Now Windows validates your installation. Whether you buy a new OEM copy or get it on a prebuilt, it is only meant for that system. I had to call support when I replaced the mobo in my Win 7 comp after I had validated my copy. They let me transfer it, but that may not always be the case!