The full retail versions have no such limitation.
Imagine those that bought a HP or other and make such a change. It's a tad more expensive.
I recently saw an article stating that Windows was changing the TOS to where you couldn't reactivate if you changed the motherboard in your computer. It said they considered that a whole new computer. Was in a hurry, so I meant to go back. Got the idea it was about XP, but could have been Vista or something else. Haven't been able to find another mention. If true, this would mean not upgrading to a 64-bit board and CPU, or abandoning Windows. I am NOT going to pay twice for something I bought in good faith. Anyone have a clue what I am talking about? chuck