My motherboard is abnormally hot.... hotter than my cpu. Its temps go from 37C at idle to 50C while playing games (for hours).
This is what I am thinking... I take out the bottom 3 External 5.25" Drive Bay slots so I have enough room to fit an extra 120mm fan where those slots used to be. I then would rig something up with pantyhose to use as a fan filter and also to cover the rest of the gap that the fan doesn't take up.