hi, i am building my first computer, and ran into a little issue. I read that you should install brass risers on your case, and then put your motherboard on top of them. My case has little bumped up places, that line up perfectly with my motherboard screws. And my case only came with 3 risers, that make it compatable with micro atx motherboards. do i need plastic risers? or are those bumped up ones the correct ones? sorry if this doesnt make much sense, and thanks in advance!