The reason for the strange whistle at the new cooler?
Bought a new cooler the Arctic Cooler F9 for the purpose of forcing cold air into the case. But there is a problem: he whistles when he works on blowing (set for both the front and rear panel of the system unit). Tried to loosen the mounting screws, but it gave no effect. The only thing that was noted - if on the other side of the lattice put your hand over (not even close) - whistle or not or it is very weak (but it is understandable - creates a small, but still an obstacle to the retraction of the air and weakens the whistle).
In the mode on blowing and just when the hand holding podklyuchenii cooler - no whistle no. How can this be and most importantly - how can I fix it?
The causes for the noise from the fan very much -
The noise caused by the friction in the bearings.
The noise caused by the imbalance of the fan, which generates vibration to adjacent elements.
The noise caused by turbulence occurring near the blades.
The noise caused by vortex flows in the rejected fan the air.
If the fan is a barrier to the passage of air, they in turn can give rise to noise, or Vice versa quenching.
In General, if you go for science is a tremendous amount of work to identify the type of noise, and to develop methods of preventing noise.
If not science - experiment with the location of the fan, it is much faster.