If you buy OEM Vista and change your motherboard and have to call in, just don't tell them it's because you changed your motherboard, or you will be SOL from that point on. This policy that a Vista OEM license is bound to the motherboard really ticks me off. That is pretty much taking away our right to upgrade our computer beyond a certain point. I think that as long as you only have your copy of Vista on one machine, you should be able to do what you want with it. But unfortunately that's not how it is. I doubt that I will buy OEM anymore.