Temperatures on fanless systems



  • I have a j3355B that I have put in a Supermicro 1U chassis that I had lying around. I used to run 2 of the 4 built in fans and I would see temperatures of 29C or 30C idle, jumping to 32C when watching netflix movies on 2 or 3 devices simultaneously.

    After a minor blackout 3 days ago due to thunderstorms, I thought of removing the fans from the fan headers and going without them, since j3355B is supposed to be a fanless board. My temperatures are currently at 39C or 40C idle. Also 1U fans are like jet engines and even though the rack is in the closet, I hear them when I keep the closet door open to allow the air to circulate

    I have pfSense installed on a 30GB IDE drive that I sourced from my19 year old laptop that I finally just threw away because it wouldn't stop working.

    My question is should I be concerned with the 10C jump in temperatures and put the fans back on? Or should i enjoy the quietness the last 3 days have provided me?

    Thanks


  • Netgate Administrator

    I would not worry about at 40°C at idle.

    A better test is what the full load temperature is.

    Also what other components on the board might be getting hot.

    There are probably some fan speed/temperature target settings in the BIOS that you could use to slow the fans rather than removing them entirely. Assuming the fans are attached to the board and not directly to the PSU.
    Edit: Ah that's an Asrock board in a Supermicro chassis?

    Steve



  • @stephenw10 said in Temperatures on fanless systems:

    Also what other components on the board might be getting hot

    Only components that I am worried about is the board and the i340-T4. If the IDE dies, I will put in a cheap SSD. I am not worried about the disk as I do have config backups.

    @stephenw10 said in Temperatures on fanless systems:

    There are probably some fan speed/temperature target settings in the BIOS that you could use to slow the fans rather than removing them entirely. Assuming the fans are attached to the board and not directly to the PSU.
    Edit: Ah that's an Asrock board in a Supermicro chassis?

    Yes. AsRock in a Supermicro chassis for now. Had the chassis lying around. Eventually I plan to transplant the AsRock into a 1U front mountable chassis from plinkusa.net. I tried setting the fans at Manual and at Level 1(out of 9 levels). But the sound didn't reduce by much. So if I am going to have the Supermicro fans running, I might as well run them at full speed.

    I'll try starting up 3 devices with netflix and start a torrent download etc to see how high the temperature spikes up. But running 3 movies simultaneously is not the norm in my house. Most times it's 1 movie running on the TV and maybe download/upload a torrent or two once in a while.


  • Netgate Administrator

    I would probably consider swapping out two of the fans for quieter ones then or fitting a speed reducer resistor maybe.

    Those fans are probably moving waaay more air than is required for that CPU.

    Steve



  • @stephenw10 said in Temperatures on fanless systems:

    I would probably consider swapping out two of the fans for quieter ones then or fitting a speed reducer resistor maybe.

    Seems like a good idea. I am looking for some 1U 40mm fans that are quiet. Don't need too high a cfm, so I am hoping it shouldn't be hard to find.

    @stephenw10 said in Temperatures on fanless systems:

    Those fans are probably moving waaay more air than is required for that CPU.

    True. And that was the crux of the question. If 39C or 40C idle is not too bad, then I can skip all fans and just run it fanless.

    Over time, like I mentioned, I will move it in another 1U and then I could buy the fans that fit that chassis correctly. This current 1U chassis is a 4 bay server, and having 4 drive bays when I am using none of them seems like a waste. I plan to use it for a small server running ESXi on bare metal and running 2 - 3 VMs in the future.

    But that is going to happen after some time. Currently my 2 kids don't leave me with enough time to tinker around.