2 Replies Latest reply on Feb 10, 2013 8:49 PM by El_Plates

    i7-3930k Temperatures in Prime95 stress testing.

    El_Plates Level 1

      I have a question about using Prime95 safely.


      Q/ What are safe and acceptable maximum temperatures to run during  "Small FFTs" testing with 12 threads?

      Is it even necessary to run 12 threads?


      When the Maximum stayed on 90 degrees celsius after 15 minutes runtime, I shut down Prime95 quick smart. Was that shutdown necessary? 90 seems dangerously high to me.


      My overclock is 4.5GHz with the voltage as low as I could run it.


      Here's some typical temperature results I get during "Small FFTs" testing >


      90 degree..JPG


      And to show corresponding wattage. I ran this one for 30 minutes. Temperatures hovering around 88-89, occasionally reaching 90. >



        • 1. Re: i7-3930k Temperatures in Prime95 stress testing.
          Harm Millaard Level 7

          That is a bit higher than my system. Running at BCLK 102.3, CPU ratio 46 and CPU Vcore @ 1.375V with an ambient temperature of 19° C. During the stress test of Prime95 the temps were around 73° with a maximum of 84° C after 45 minutes of stress testing. Core# 0 was max 84° and core #3 was max 66° C. The rest was around 73° C.


          Your figures are not worrisome although somewhat higher than expected. You will never achieve the load on your system as when running Prime95. That is why it is such a good stress test. Even with PR during heavy encoding the load will be significantly lower and temps will not go up that much.


          The difference worth testing is Small FFT versus the Blended Test, which is really stressfull.

          • 2. Re: i7-3930k Temperatures in Prime95 stress testing.
            El_Plates Level 1

            BLCK Frequency 100.000, Turbo Ratio - By all cores - 45.


            CPU VCORE Voltage says 1.360V, but my CPU VCORE Manual Voltage setting is 1.420.

            Room temperature- 22 degrees C.


            I understand Prime 95 runs the CPU at hotter temperatures than we get in PR, and probably higher than in After Affects as well. Why I'm doing such extreme testing is because Summers here in Queensland get hot enough that air conditioning can't keep the room bellow 26 degrees.


            When I run the Prime 95 "blend" test, Temperatures and Powers are slightly lower.

            It seems to run ok with 12 threads on Blend.


            Something I observed in both testing types is when the Powers - Package exceeds 210W, Air exhaust is very warm, which suggests that the CPU cooler is disippating heat effectively but is overwhelming the mid tower case with that heated air.

            Perhaps the problem is my case fans are too slow, so air inside the case isn't being exchanged fast enough. The 200mm fans are very weak in terms of airflow.

            I really should measure the case's internal temperatures before making changes based on these asumptioms.



            Edit- I spoke too soon about it running ok with Prime 95 set to blend test. A rerun made the PC freeze at the 55 minute mark. No blue screen appeared. The system simply locked up and wouldn't respond.