Hello quakesoft,
As the systembuilder you are permitted to replace the motherboard (the critical component with respect to licensing) with a comparable/equivalent replacement item if it becomes defective without "creating a new computer" for licensing purposes.
A "comparable/equivalent" motherboard would be one that uses the same class of processor and memory.
If you're improving the motherboard "class" to the point where your existing processor will not work in it, then you have for Microsoft's licensing purporses created a new computer that will need a new license.
The practical answer is to buy the motherboard and processor that you want, install Windows, and try to activate, either automatically online or by Telephone. If it activates, don't give it another thought. If it does not activate, try activating
by telephone, but do not say or enter anything into the automated phone system. This will shunt you to a live activation rep. Explain that you built the system, that your motherboard died on your system, and you installed a replacement motherboard.
More often than not they will activate your installation. BUT! Save some money incase they don't, so you can buy a new license for Windows.
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