Silencing the Supermicro SuperChassis 826

spookyghost -

A few months ago I purchased a system based on the Supermicro SuperChassis 826, and it was way too loud.

It includes three very powerful and loud 80mm fans. The model is FAN-0126L4. Since I had an X9 board (X9DRW-CTF31) there is no way to send raw IMPI fan control commands to the IPMI. I can only choose between Standard, Full, Heavy IO and Optimal fan policies.

I set it to optimal and installed it in my rack, and everything seemed good. Then it randomly ramped the fans up to over 6000RPM which was as loud as a vacuum cleaner. I checked the temperatures, and everything was good before the fans ramped up, and didn't even get much lower with the fans ramped up

I decided to swap the thermal paste..

But, that did nothing. It did get the CPU temperatures down a few degrees, but the fans were still way too loud.

After a few days of research I came to the conclusion that I either needed to replace the fans, or slow the fans.

Replacing the fans would be hard, because if i got fans that were too low CFM, the system would be too warm. And good quality fans are not very cheap

I decided to get a fan controller, but I needed one that would handle the high wattage 80mm fans. I settled on the Lamptron CP436 controller, which will do a staggering 36w per channel and still pass on PWM information

I ende up splicing the cables so I could still plug the PWM pin to the board and monitor fan speed, while being able to control the fans via the rear panel. Here you can see the single wire going to the fan headers

The install was not very neat, but it worked!

Here is what it looks like from the rear

So far even under pretty high load, the tempratures never get too high. I have two of the fans set to 3000RPM, and the third set to 3500RPM

Its been around 6 months, and everything is working well.

There is some downsides of this

  • I need to reach behind the server to adjust the fan speed
  • The server can't take over and ramp up fans to cool itself
  • It uses up a PCI slot that could be used for something else

Let me know what you think!