Originally Posted by NASzi
so last night I got bored, I took some snips and cut out the mesh where my rad sits, came out very nice. I took out my 200mm megaflow, Dropped my radiator down to where it is touching my case, put my corsair fans on top and put the XS-PC fans underneath on the inside of the case. Didn't get a chance to bench but my ambient temps went down 2-3 C. What's crazy is that everything is actually quieter this way and it doesn't sound like a turbine engine, I guess the fans were struggling to pull air through the mesh.
That mesh was punched from the top down if I'm not mistaken? You probably noticed a slightly sharper edge on the bottom. With that sharp edge facing down and the fans sitting on top pulling the air through, it would have caused the mesh to vibrate and create a harmonic resonance throughout the surface of the mesh that air was being pulled through, since each edge of the hexagonal cuts was vibrating at the same frequency. It was likely just the fact that you were pulling air in the direction that you were. Reversing the setup and pushing the air through from the top would have likely had very close to similar results as far as noise, but changing your setup in the manner you have is what resulted in the drop of temperature.