No there are no security measures, as for upgrading your motherboard you likely have a Windows 10 License attached to your microsoft account if your last system had windows 10. Login with that account and it should activate your system. You may need to login on the web to your account and deactivate your old system.
further to what rouge leader said,if you cant activate your windows 10 on your new motherboard you can always phone microsoft support and they can help you.i did a new build and had to go that route.the lady on the other end of the line told me to have coffee and relax,she would activate it.pretty good customer service.