"Microsoft recently made changes to the license agreement. A new
motherboard is now apparently the equal of a new computer, and if you
upgrade it you need to purchase a new Windows license.
Microsoft’s new policy states:
An upgrade of the motherboard is considered to result in a “new personal
computer†to which Microsoft OEM operating system software cannot be
transferred from another computer. If the motherboard is upgraded or
replaced for reasons other than a defect, then a new computer has been
created and the license of new operating system software is required.
The reason Microsoft gave for this term is that Microsoft needs to have
one base component “left standing†that would still define that original
PC. Since the motherboard contains the CPU and is the “heart and soulâ€
of the PC, when the motherboard is replaced (for reasons other than
defect) a new PC is essentially created.
Microsoft has sent a memo to its OEM partners asking them to enforce
this new policy every time they upgrade a computer for a client.