if there's no holes for a fan to draw air in, you might have to break out a dremel and cut one. wether you actually want to bother though... There are some fan things that fit into the 5 1/4" drive bays, doubt theyre as good as a proper fan but probs save you cutting your case if you really want intakes (and if youre temps arent causing problems atm, i wouldnt bother).