Because drivers and hardware components usually are totally different between motherboards, switching motherboards usually means a reinstall of windows. I've seen a good number of cases where if you switch the hard drive from one PC to another the result is Blue Screen at boot.

If, in the rare case that it boots up and asks for the new drivers, I still would recommend a reinstall, because windows always leaves leftovers and it's probably best to do a clean install and not have weird problems later.