Originally Posted by
PTravel
The motherboard, CPU, and support chips didn't change, and those would be far more indicative of installation on another computer than a NIC, hard drives, graphics cards, or other readily- and often-upgraded components.
Unfortunately, the NIC is the only thing there that has a guaranteed unique serial number which is determinable in a very standard manner. And the truth is, most folks don't actually change the NIC all that often -- these days, they are built into the motherboard, which has become the broad definition of 'system.'
Steve