Re: simple mobo question
If the motherboard is exactly identical, no. You may not even have to reinstall the OS.
Edit: When changing a motherboard, Microsoft considers that a "new build"; therefore requires that you purchase another license for Windows. However, I've read that if the motherboard is EXACTLY identical, then it's not considered a new build as this is considered a replacement.
Humans are the only creatures that won't live up to the their potential. Give everything your all. When you die, die on E.
So I ask you, what do you intend to do now?