Quote: Originally Posted by Sheza
I just wanted to know specifically what it was.
Question: What part is tied to it?
Answer: The motherboard serial number.
COUNTER ARGUMENT: If you replace the motherboard with an identical model, a new OEM key is not required.
New Question: So if it's not serial number, what part is it?
BIOS? MAC Address?
It is NOT tied to ANY one piece of hardware or any number, like a serial #, Specifically. Although replacing the motherboard with a different model will definitely trigger re-activation.
Replacing all other components, RAM, HDDs, GPU, DVD drives or upgrading the CPU even on the same motherboard, all at the same time or one component at a time, may or may not trigger re-activation.