I've found that the Stealth case fans are very quiet when running in my hand,\nbut when they touch the case they make a noticeable humm.\n\nMy solution was to hang all of the case fans on rubber bands, thusly:\nMount two 1.5 inch long 6x32 bolts thru the case, protruding inside,\nwith a nut tightened on the inside. One bolt is above the fan and one below.\nThe bolts are slightly wider apart than the size of the fan housing; you don't\nwant them touching the fan housing. For 80 mm case fans my bolts are\nabout 3.5" apart.\n\nCut a piece of 3,5" diameter inner tube about 1/2" wide and stretch around\nthe 80mm fan housing, then hang the fan on the two bolts by stretching\nthe rubber band over the bolts. The only contact between fan housing and\nthe case is rubber. I used a 6" diameter inner tube for my 120 mm fan. Set\nthe fan face very close to but not quite touching the case so it moves air thru\nthe case instead of recirculating it.\n\nVisit your tire dealer for used inner tubes, the bigger variety the better.