The Cosmos 1000 from Cooler Master has an acoustical performance that reminds you of the quiet of space. Extreme sound suppression was a primary focus of the design. All four of the fans are 120mm to move the most air with the least noise. The two fans on the top blow air out through a louvered duct and the intake fan is on the bottoms and pulls air up through a filter. The side panels are covered in a sound deadening material.