5 Replies Latest reply on Sep 15, 2016 12:20 PM by Intel Corporation

    Bypass or Prevent Xeon E5-2690v3 Power Throttling?

    Ammonia

      I've become rather disappointed by how much my CPU is throttling - from what I assume is the power limit. Using Open Hardware Monitor I can see the power being used by the CPU, the core clocks, load and temperatures. As the power reaches 135W all the core clocks are reduced, when I'm running all cores at full load they're only doing 1.7 GHz each (1699 MHz). This is despite all core temperatures being below 60 C. 

       

      Is there a way to prevent this? Can I increase power limit? My motherboard is ASRock X99 WS. (If I can, what are the drawbacks?)

        • 1. Re: Bypass or Prevent Xeon E5-2690v3 Power Throttling?
          Intel Corporation
          This message was posted on behalf of Intel Corporation

          Hello Ammonia:
           
          In regard to your inquiry, the 135W is a Thermal Design Power (TDP) that represents the average power, but, even if the processor reaches that measure the cores should be able to reach 2.60 GHz or 3.50 GHz it the max turbo frequency starts to work.
           
          So, this could be a problem with the processor or motherboard.
           
          We do have a tool to test the processor, it does an overall test on it, if the processor passed the test it should be working fine, to install the tool use the second option to the left on the following link:
           
          https://downloadcenter.intel.com/download/19792/Intel-Processor-Diagnostic-Tool
           
          Do you have the option o test the board with different processor, or the processor on a different board?
           
          Did you restore the BIOS to defaults?
           
          Have you tried a BIOS update to the latest version?
           
          According to ASrock’s web site, the latest version is 3.30:
           
          http://www.asrock.com/mb/Intel/X99%20WS/?cat=Download&os=BIOS
           
          In regards to the question about increasing the power limit, we always recommend to use the PC at stock configurations and to use the BIOS at default values.
           
          Any type of customizations are done through the BIOS, so, if there is an option to do that, you will need to check that with ASrock directly, since the BIOS was design by them.
           
          Any questions, please let me know.

          Alberto

          • 2. Re: Bypass or Prevent Xeon E5-2690v3 Power Throttling?
            Ammonia

            I ran the diagnostic tool and it passes just fine, the BIOS is also the latest version. BIOS settings are all default except hyperthreading is disabled. This is what happens; if I run Prime95 to stress-test my CPU, all the cores start at ~2.6-2.7 GHz and Open Hardware Monitor shows 153W "used" under CPU Package Power, after a few seconds all the cores drop to 1.6~1.7 GHz and stay there, and the power drops to 135W (in the picture it only just dropped from 153W, and the cores dropped next).

             

            loadedPrime95_2.JPG

            It runs like that for 2-3 seconds, before:

             

            loadedPrime95_.JPG

            And the core clocks remain at this 1.6-1.7 GHz. I just can't understand why? The temps are just fine, the power supply used is rated for 1000W and should have no problem delivering. Interestingly, when the CPU is loaded using the Diagnostic Tool, it seems to maintain high clock speed throughout:

             

            IPDT_load.JPG

            Is it load-specific? I guess I'm just confused by the seemingly "random" performance of the chip.

            • 3. Re: Bypass or Prevent Xeon E5-2690v3 Power Throttling?
              Intel Corporation
              This message was posted on behalf of Intel Corporation

              Hello Ammonia:
               
              Thank you very much for providing those pictures.
               
              It is kind of strange that the clock speed decreases during the stress test, but when you run 3rd party tools like Prime 95 or Hardware Monitoring there might be misreadings on some values and the behavior of the processor might not be as expected.
               
              That is why we rely in our tool, the processor diagnostics tool, and if the processor passed that test, and you do not get any errors while running our tool or when you use the PC, then the processor should be working fine.
               
              The reason why the processor behaves like that when you use those tools for us is unknown, let me apologize for that, but the information we support is based in our tool.
               
              If you suspect there might be something wrong with the processor, remember it has 3 years of warranty, the thing is that the problem could be related to the processor or the board, so, if you have the option to test another processor on your board, or test your processor on a different board, that will be a good thing to try, however we know that option is not always available.
               
              If you are interested in the replacement, please get in contact directly with us through chat, email, phone or online support, you just need to select processor on product type and you will get those options:
               
              http://www.intel.com/content/www/us/en/support/contact-support.html#@12
               
              So, in this case the processor seems to be fine, and if you replace it the new one might do the same with those tools, but still, we can always replace it for you.
               
              Any questions, please let me know.
               
              Alberto
               

              • 4. Re: Bypass or Prevent Xeon E5-2690v3 Power Throttling?
                Ammonia

                Thank you for taking your time to answer.

                 

                It seems like the problem isn't so bad, using other CPU "stress-testing" software gets higher clock speeds - probably something unusual with Prime95.

                • 5. Re: Bypass or Prevent Xeon E5-2690v3 Power Throttling?
                  Intel Corporation
                  This message was posted on behalf of Intel Corporation

                  Hello Ammonia:
                   
                  Yes, correct, occasionally some misreadings might occur when using 3rd party tools, but as long as the PC is working fine, there is nothing to worry about.
                   
                  Any other inquiry, do not hesitate in contact us again.
                   
                  Regards
                   
                  Alberto