Posted 02 August 2010 - 08:36 AM
If the computer has been repaired and the motherboard replacement is the same type, it will have the same hardware, and so technically be considered to still be the same computer. OEM Windows is licensed only to the original computer it is sold with, so cannot be operated on a substantially different computer, since this would breach the license conditions.
It is possible that if the motherboard has onboard LAN, then Windows might need to be re-activated, because the NIC will have changed, and this difference can generate a sufficiently different hardware signature that the installation needs to be re-validated. If so, Microsoft will just need to know the system has been repaired.
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