1 2 Previous Next 19 Replies Latest reply on Mar 25, 2017 12:26 PM by N.Scott.Pearson

    Safe operating temperature for Q9400

    wingman99

      Safe operating temperature for Q9400

        • 2. Re: Safe operating temperature for Q9400
          wingman99

          How do you measure Tcase? I want to know Tjmax of the cores.

          • 3. Re: Safe operating temperature for Q9400
            Al Hill

            You can try Download Intel® Processor Diagnostic Tool

            or some 3rd party tool like https://www.aida64.com/downloads

             

            The above link is provided for your convenience.

             

            Doc

            • 4. Re: Safe operating temperature for Q9400
              wingman99

              Tcase is not the core temperature. Tcase is the temperature measurement using a thermocouple embedded in the center of the heat spreader. This initial measurement is done at the factory. Post-manufacturing, Tcase is calibrated by the BIOS, through a reading delivered by a diode between and below the cores.

              • 5. Re: Safe operating temperature for Q9400
                Al Hill

                So, what are you asking for now?  Your initial question was not specific and mentioned neither.

                 

                Did you try the utilities I referenced?

                 

                You asked for the safe operating temperature, which is anything less than 71.4°C

                 

                Doc

                • 6. Re: Safe operating temperature for Q9400
                  wingman99

                  71.4c is Tcase, inlet says folks can't measure that with software .

                  • 7. Re: Safe operating temperature for Q9400
                    N.Scott.Pearson

                    In order to determine the Tcontrol temperature - the temperature that the fan speed control subsystem is required to maintain (and which defines the upper limit of the safe operational range) - you need a tool that can read the IA32_TEMPERATURE_TARGET MSR. Tcontrol is a field contained within this MSR.

                     

                    ...S

                    • 8. Re: Safe operating temperature for Q9400
                      N.Scott.Pearson

                      Ok, at home and not using phone any longer, so can look a few things up...

                       

                      The IA32_TEMPERATURE_TARGET MSR provides two pieces of information. The first, in bits 23::16, is the Tjmax temperature for the processor. This is also the temperature where the Thermal Control Circuit (TCC) begins throttling the performance of the processor to protect the processor from damaging temperatures. The second, in bits 15::8, is the Tcontrol Offset. This is the offset from Tjmax for the Tcontrol temperature. Here's an example: if the Tjmax temperature reads as 100 (degrees celsius) and the Tcontrol Offset reads as 20, this means that the absolute value of Tcontrol is 80.

                       

                      Why this (seemingly) bizarre representation? Well, the Digital Thermal Sensors (DTS) in the processor (there's one per physical Core) are calibrated to the Tjmax temperature and they return temperature readings that are relative to (an offset from) the Tjmax temperature. If you read a DTS and it says the temperature is -40 and your processor's Tjmax temperature is, say, 100, then the current temperature of the Core in question is 60. There's one special case: the DTS cannot measure or return temperature readings that are above Tjmax. Thus, if the reading is 0 (zero), it means that, if (for example) your processor's Tjmax is 100, the temperature of the Core is 100 or higher. If the temperature goes a certain amount above Tjmax (Intel will not tell us how much as it can vary from one individual processor to another), the Thermal Protection Circuit (TPC) will power off the processor to protect it from damage. This is called a "therm-trip".

                       

                      In some processors (Atom and some Celeron and Pentium), this MSR will not provide a Tcontrol Offset (value in MSR will be 0 (zero)). When this is the case, you have to pick a value to use. Based upon thermal analysis I did with some of the Desktop Board and early NUC products, I recommend the value 17 be used.

                       

                      In some older processors (the Core 2 Duo/Quad, for example), this MSR will not provide a Tjmax value (value in MSR will be 0 (zero)). When this is the case, you have to pick a value to use. I recommend that you use the value 100.

                       

                      I hope this helps. If you want to take the easy way out, you won't be too far wrong if you just assume that the Tcontrol temperature is ~80 and you stay below that.

                      ...S

                      • 9. Re: Safe operating temperature for Q9400
                        wingman99

                        I tried 95c and this is what I have.

                        Thermal throttle.JPG

                        • 10. Re: Safe operating temperature for Q9400
                          N.Scott.Pearson

                          Tried 95c as what? Tjmax? This is way, way too high for Tcontrol.

                           

                          The motherboard's fan speed control subsystem is required to keep the temperature of the processor at or below the Tcontrol temperature. By definition, if the temperature of the processor is at or above the Tcontrol temperature, the processor fan and any chassis fans are supposed to be running at their full speed. Remember, while the processor can handle being at the Tcontrol temperature for its entire warranted lifetime (literally), being at temperatures above this level can, over time, damage the processor and reduce its lifetime.

                           

                          From what I am seeing in this display, your motherboard's fan speed control capability is not working adequately. This could be due to misconfiguration or inadequate fans/heatsink...

                          ...S

                          • 11. Re: Safe operating temperature for Q9400
                            Intel Corporation
                            This message was posted on behalf of Intel Corporation

                            Hi,

                            Please check the following information about Tcase and Tjunction

                            http://www.intel.com/content/www/us/en/support/processors/000005597.html

                            Additionally, see the link below to get third party software to monitor processor temperatures
                            http://www.buildcomputers.net/check-cpu-temperature.html

                            NOTE: This link is being offered for your convenience and should not be viewed as an endorsement by Intel of the content, products, or services offered there.

                            Allan.

                            • 12. Re: Safe operating temperature for Q9400
                              wingman99

                              N. Scott Pearson wrote:

                               

                              Tried 95c as what? Tjmax? This is way, way too high for Tcontrol.

                               

                              The motherboard's fan speed control subsystem is required to keep the temperature of the processor at or below the Tcontrol temperature. By definition, if the temperature of the processor is at or above the Tcontrol temperature, the processor fan and any chassis fans are supposed to be running at their full speed. Remember, while the processor can handle being at the Tcontrol temperature for its entire warranted lifetime (literally), being at temperatures above this level can, over time, damage the processor and reduce its lifetime.

                               

                              From what I am seeing in this display, your motherboard's fan speed control capability is not working adequately. This could be due to misconfiguration or inadequate fans/heatsink...

                              ...S

                              The processor can operate at TJMax for it's warranty life time correct?

                              • 13. Re: Safe operating temperature for Q9400
                                N.Scott.Pearson

                                No!

                                The processor could operate at its Tcontrol temperature for its entire warranted lifetime, but should only go above this temperature if it can be guaranteed that the thermal solution can keep it below the thermal load line. By definition, since you do not have the inputs necessary to follow the thermal load line, your thermal solution should be running at maximum (i.e. fan at full speed) for any temperature above Tcontrol. Your Tcontrol temperature should be somewhere in the vicinity of 80-85c; you can read it (as an offset from Tjmax) via one of the MSRs.

                                 

                                Hope this helps,

                                ...S

                                • 14. Re: Safe operating temperature for Q9400
                                  wingman99

                                  What is Tcontrol? I don't see anything you are talking about in Intel's datasheets.

                                   

                                  In Intel processors, the core temperature is measured by a sensor. If the core reaches its TJMax, this will trigger a protection mechanism to cool the processor. If the temperature rises above the TJMax, the processor will trigger an alarm to warn the computer operator who can then discontinue the process that is causing the overheating or shut down the computer to prevent damage Junction temperature - Wikipedia

                                   

                                  Intel® Processors have built-in thermal protection. If the processor gets too hot, the built-in protection shuts down the processor. If your computer is not over-clocked, and is running under the design specifications, the built-in protection can help prevent damage to your system. What do I do if my computer is overheating?http://www.intel.com/content/www/us/en/support/processors/000005776.html

                                   

                                  Tjunction Max is the maximum temperature the cores can reach before thermal throttling is activated. Thermal throttling happens when the processor exceeds the maximum temperature. The processor shuts itself off in order to prevent permanent damage. Tjunction Max (Tj Max) is also referred to as TCC Activation Temperature in certain processor datasheets.

                                   

                                  Frequently Asked Questions about Temperature for Intel® Desktop and...

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