Guy is getting ready to upgrade his PC by changing out the motherboard and wants to know if he needs to reinstall Windows. Leo says yes, he will. The computer will be confused because the OS is looking for the motherboard it was installed for. What
Guy could go into the device manager and delete everything. Then reset the ESCD in BIOS so it'll reacquire everything. Then he'll have to install all the latest drivers. Doing this may cause Windows to think it isn't a genuine copy, though. So he'll have to call Microsoft and explain to them that he replaced the motherboard and they'll give him a new Key. At the end of the day, it's best to just start over and reinstall.