i don't understand why people try to find ways out of it.If you're going to nitpick, you might want to have a closer look at the Windows 7 OEM EULA - *nowhere* does it explicitly state that an end user will be breaking the agreement by changing a motherboard.
MS can publish as many FAQs as they like about a motherboard being the "heart and soul" of a computer, but unless that definition is written into the contract (the EULA) it's nothing more than a point of view, and isn't legally binding. IMHO of course.
people know the heart of a computer is the motherboard. yes maybe it isn't totally clear in the EULA, maybe thats why they put a license FAQ's
also the whole reason for retail version is so people can transfer it