MBT-4220 - is it possible to cool passively?

  • I purchased the MBT-4220. It is small, well built and fast. I like it a lot.

    I do have a questions, is it possible to have it cooled passively? maybe a bigger heat sink and have a larger fan pulling air over it? something more quiet which spins slower? I wanted the quad core and that is why I did not get the MBT-2220.

    I am curious if anyone knows of a way to do that or other suggestions.

  • Netgate Administrator

    I know a number of us tried different things internally. I ran a 12V fan on there from the 5V fan header for a while. That is very quiet as you can imagine but whilst I never had any overheating problems the cooling it provides is a lot less than the 5V fan. It's barely possible to detect it moving any air!
    Better than that is to run the 5V fan from 3.3V which seems to cool sufficiently whilst also being significantly quieter. It's possible to do that just by rotating the fan and connecting it to the GPIO header BUT at least one of my colleagues here connected it the wrong way around permanently damaging the fan. So I leave that as an exercise entirely at your own risk. 😉
    In addition I also tried mounting the fan on rubber mounts which was a marginal improvement.


  • I unplugged the fan and put it in all adaptive mode

    2 open vpn clients and i get full speeds and it never goes above 55c

    If it dies I’ll buy another one since they dropped almost 100 dollars since my purchase...

  • @bcruze Can you elaborate on adaptive mode? Is this a BIOS or other setting?

  • yes Sir.

    click on system > advanced > miscellaneous tab. power savings

  • Netgate Administrator

    Probably the powerd settings. Adaptive rather than the default 'high-adaptive' will run the CPU slower on average in variable load conditions resulting in marginally less power consumption and hence heat.
    No fan at all with the same heatsink would concern me. It's a smaller heatsink than the MBT-2220 which is entirely passive but a greater potential power dissipation.