My new favorite 120mm case fan

bubbaQ · May 20, 2016

Like lots of people, I've searched for fan Nirvana of silence and move a boatload of air at the same time. Luckily I gave up and accepted the laws of physics.

I have, however, found a new favorite 120mm fan. Delta AFB1212SHE-PWM.

I am rebuilding a 4U rack case and needed three 120MM fans for the fan plate. One problem I have always had is that 3-pin PWM fans (or 4-pin fans on a 3-pin connector) can only be spun down by about 1/3 so a 2000 RPM fan on high, can only be spun-down reliably to a 3rd of that number, or about 700 RPM. And when you do that, you often get an annoying pulsating noise from the PWM.

Plus most common case fans deliver poor static pressure in restricted airflow environments... particularly those marketed as "quiet" since those marketed as "quiet" are usually 2000 RPM and below.

My new Supermicro mobo forced my hand as all the fan headers are 4-pin, and they do not support 3-pin PWM. 3-pin fans run 100%.... period. So I started looking at 4-pin 120mm fans. I also wanted good static pressure to pull air through the grills on the disk trays so I was looking for 38mm thick fans.

I have a couple of Delta fans that came with cases in the past, that like most Deltas, move tons of air but sound like jet engines. What many people don't know, however, is that 4-pin PWM Delta fans can reliably go down to a very small (~15% or less) of their top speed, and do so without the pulsating noise.

So I tried a AFB1212SHE-PWM because it is only 3700 max speed, and it is 38mm thick so it has better static pressure. On the Supermicro with the fan speed at 30% duty, the fan spins at 600 RPM and is nearly silent. Coupled with a 20mm fan shroud www.amazon.com/Phobya-38112-120mm-Plexiglass-Shroud/dp/B004CLFFIA (so the blades don't have to fly so close to the grill, another source of noise) I can barely hear the fan outside the case. In fact, most of the noise is merely the air entering the grills on the front of the case and exiting the grill in the back (I am running with no exhaust fan other than the one on the PSU).

And if I have the need for serious cooling, ramp them up to 100% and they wipe out anything in the traditional case fan lineups. At 150 CFM and 14.5 mmH2O, it will pull small animals into the grill.

And they are only $10 on Amazon.

So this is my new favorite fan in restricted airflow and for radiators. Probably not a good choice for someplace you want total silence like HTPC.