Have a Cooler Master hyper 212+ and was cleaning dust out of Coolermaster Scout case. Found a layer of dust built up on the hyper 212+ between the fan of the cooler and the aluminum fins if the cooler itself. Getting rid of that layer was difficult. Compressed air just moved the dust a lillte away from the fins. Then used Q-tips and alchohol to reach down inbetween the fins and the attached fan. Don't think I got all the dust out either. Wondering what other, better informeded people do to remove and/or prevent dust build up.