Without knowing what you have or your exact problem, I would think to change mobo to solve the problem maybe a bit of overkill. What built-in device/s is the problem? Have you already look in the bios to see if it can be disable it there?
But if you just want a faster and better computer then by all mean...but you should also realize it involves lots of work as well. Good luck.
my motherboard has a inbuilt card and i bought a new card, the new card dont work because of the inbuilt one, will buying a new mother board without a inbulit card and that supports my new card solve this problem? i don't want to waste money