Originally Posted by javamocha
i just install D-15 with one fan...i set the fan for pull on the first tower (center between the towers, attached to the first tower). when on load, the HSF makes strange sound...and the sound decreases when the fan slows down. is it normal?
should i just set the fan for push on the second tower?
Yes, mount fan so it pushes on 2nd tower. The reason is the fan housing / frame spaces fan almost flush (1mm) with intake side of fan but is 3-4mm from exhasut side becuase of the motor mounting frame on that side of fan. This 1mm vs 3-4mm is what is making the sound difference. Many cooler companies that supply fans for pull on back of cooler (NH-U14S) have a spacer / thicker vibration dampening block for the pull fan or have more space between fins and fan on pull side.