3 Replies Latest reply on Sep 18, 2017 2:13 PM by Intel Corporation

    NUC7i5BNB thermal throttling in passive case?

    Marjo Suuronen

      Hello,

       

      I've just finished installing our first NUC7i5BNB board into Akasa Newton S7 passively cooled case. The unit is functioning very nicely apart from the fact under continuous heavy load it seems to enter thermal throttling although CPU temperatures are still well within limits. For testing purposes I have otherwise identical NUC7i5BNH Kit with the same bios and drivers. I'm using Prime95 for load generation and CPUID HWMonitor for monitoring system load, temperatures and power usage. When under 100% load the temperatures on the NUC7i5BNB+Akasa combo are almost identical to the ones of NUC7i5BNH Kit; CPU package temp is ~80-84C while the case itself is ~53C. But the NUC7i5BNH throttles by lowering frequency (3,4GHz -> 2,2GHz) and power (25W -> 14W) while NUC7i5BNH does not.

       

      I've found this thread: Re: NUC6i5SYK with Akasa Fanless case which references:

      "The Technical Product specification for the NUC Board states:

      “A chassis with a maximum internal ambient temperature of 50°C at the processor fan inlet is recommended.  If the internal ambient temperature exceeds 50°C, further thermal testing is required to ensure components do not exceed their maximum case temperature.”

       

      Could someone confirm that the 50C ambient temperature is the critical level also for NUC7i5BNB to start throttling? It at least seems so.

       

      Best regards,

      Henri / TeraStore

        • 1. Re: NUC7i5BNB thermal throttling in passive case?
          Intel Corporation
          This message was posted on behalf of Intel Corporation

          Hello Henri TeraStore,

           

          Thank you for joining the Intel® NUC community.

           

          Based on the description found in the Technical Product Specification, 50°C is the maximum internal ambient temperature which is considered within the specs. If the internal ambient temperature increases the unit could enter to a critical level and start to throttle. 

           

          Regards,

          Amy C.

          • 2. Re: NUC7i5BNB thermal throttling in passive case?
            Marjo Suuronen

            Hi Amy,

             

            Thank you for the answer. I've done some additional testing and the throttling starts almost exactly on 50C. For anyone else considering NUC7i5BNB with a passive Akasa case, you will most likely encounter throttling under full continuous load (eg. video encoding) unless you either somehow lower the ambient temperature (we had 23C) or lower the Turbo Boost mode. In more normal usage scenarios we did not encounter any throttling and case internal temperatures were well below the 50C threshold.

             

            One could argue that when setting cooling to Fanless in bios, this "intake air temperature" throttling should not take place. Especially since the processor itself is not overheating. But on the other hand, the other components would suffer from this.

             

            Best Regards,

            Henri / TeraStore

            • 3. Re: NUC7i5BNB thermal throttling in passive case?
              Intel Corporation
              This message was posted on behalf of Intel Corporation

              Thank you for sharing this information Henri, I am sure another user in the community will find your input helpful.

               

              If there is something else we can help, please let us know.

               

              Regards,

              Amy C.