Question How hot should my CPU run at 100%

jdidds

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Mar 17, 2019
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Just did did a new build and did a benchmark on it. I have a Corsair H100i Pro cooler with a i7-9700k processor.

HW monitor showed upper 60 degree C temps on all cores. Is this normal? I heard that you shouldn't reach over 60 for longer periods. It idles at around 30C.
 

CompuTronix

Intel Master
Moderator
jdidds,

"Throttle" temperature (Tj Max) for your i7 9700K is 100°C, which is Intel's specified Core temperature limit at which the processor will "throttle" (reduce Core speed and voltage) to prevent thermal damage. Nevertheless, here's the nominal operating range for Core temperature:

Core temperatures above 85°C are not recommended.

Core temperatures below 80°C are ideal.



Respectfully, users conjure up countless haphazard methods to approach thermal testing; nearly all of which is based on misconceptions, misinformation and hearsay inconsistent with Intel's Datasheets. It's no surprise why there's so much confusion surrounding this topic. However, there is an established method with specific procedures for properly testing thermal performance. There's a Sticky near the top of the CPUs Forum:

• Intel Temperature Guide - https://forums.tomshardware.com/threads/intel-temperature-guide.1488337/

See Sections 10 through 14.

Benchmarks and stress test workloads vary widely, and as such are a major variable, so it's important to be specific.

Exactly which "benchmark" did you run?

Intel uses a steady-state "100% TDP workload" with steady Core temperatures to thermally validate their CPUs. There's only one utility and test which is consistent with Intel's test parameters:

• Prime95 version 26.6 Small FFT's - https://www.mersenneforum.org/showthread.php?t=15504 (Do NOT use any later versions such as 27.7 through 29.4. The reasons are explained in the Guide in Section 11.)

Utilities that don't overload or underload your processor will give you a valid thermal baseline. Here’s a comparison of utilities grouped as thermal tests (steady workloads) and stability tests (fluctuating workloads) according to % of TDP, averaged across six processor Generations at stock settings rounded to the nearest 5%:



All tests will show 100% CPU Utilization in Windows Task Manager, which indicates processor resource activity, not % TDP workload. Core temperatures respond directly to Power consumption (Watts), which is driven by workload.

Further, all computer temperatures increase and decrease with ambient (room) temperature, which can be another major variable.

Users write into our Forums who live anywhere from the arctic circles in a relatively cold indoor environment, to the equator with no A/C. Ambient temperatures might be anywhere from 10°C (50°F) to 40°C (104°F).

The "standard" for normal room temperature is 22°C or 72°F. Since many of our Members don't ask, it's important to state your ambient temperature in your initial post, so we don't proceed on false assumptions.

What was your ambient (room) temperature during your "benchmark"?

Thanks,

CT 😎
 
If your MB is Asus, Asrock, or MSI, you can enable MCE in the BIOS, as that option alone will clock all cores at max turbo of 4.9 GHz under load....

That should take care of the 'only 65C under load' in short order :) (But, IMO, all cores at 4.9 GHz is a nice intermediate step short of all cores at 5 GHz and above, and, CPU still scales nicely back down to idle/800 MHz, etc., when not under load and in Balanced Power plan)
 

jdidds

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Mar 17, 2019
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4,535
jdidds,

"Throttle" temperature (Tj Max) for your i7 9700K is 100°C, which is Intel's specified Core temperature limit at which the processor will "throttle" (reduce Core speed and voltage) to prevent thermal damage. Nevertheless, here's the nominal operating range for Core temperature:

Core temperatures above 85°C are not recommended.

Core temperatures below 80°C are ideal.



Respectfully, users conjure up countless haphazard methods to approach thermal testing; nearly all of which is based on misconceptions, misinformation and hearsay inconsistent with Intel's Datasheets. It's no surprise why there's so much confusion surrounding this topic. However, there is an established method with specific procedures for properly testing thermal performance. There's a Sticky near the top of the CPUs Forum:

• Intel Temperature Guide - https://forums.tomshardware.com/threads/intel-temperature-guide.1488337/

See Sections 10 through 14.

Benchmarks and stress test workloads vary widely, and as such are a major variable, so it's important to be specific.

Exactly which "benchmark" did you run?

Intel uses a steady-state "100% TDP workload" with steady Core temperatures to thermally validate their CPUs. There's only one utility and test which is consistent with Intel's test parameters:

• Prime95 version 26.6 Small FFT's - https://www.mersenneforum.org/showthread.php?t=15504 (Do NOT use any later versions such as 27.7 through 29.4. The reasons are explained in the Guide in Section 11.)

Utilities that don't overload or underload your processor will give you a valid thermal baseline. Here’s a comparison of utilities grouped as thermal tests (steady workloads) and stability tests (fluctuating workloads) according to % of TDP, averaged across six processor Generations at stock settings rounded to the nearest 5%:



All tests will show 100% CPU Utilization in Windows Task Manager, which indicates processor resource activity, not % TDP workload. Core temperatures respond directly to Power consumption (Watts), which is driven by workload.

Further, all computer temperatures increase and decrease with ambient (room) temperature, which can be another major variable.

Users write into our Forums who live anywhere from the arctic circles in a relatively cold indoor environment, to the equator with no A/C. Ambient temperatures might be anywhere from 10°C (50°F) to 40°C (104°F).

The "standard" for normal room temperature is 22°C or 72°F. Since many of our Members don't ask, it's important to state your ambient temperature in your initial post, so we don't proceed on false assumptions.

What was your ambient (room) temperature during your "benchmark"?

Thanks,

CT 😎

Off the top of my head, I can't remember which benchmark I used. Ambient room temps where around the 21C mark.
 

CompuTronix

Intel Master
Moderator
jdidds,

Your ambient temperature is within 1°C of normal.

Since the benchmark you used is now an unknown variable, if you're interested in seeing your rig's thermal performance using a valid 100%TDP workload, then your next step should be to click on the link I provided in my post above, download Prime95 version 26.6 and run Small FFT's.

10 minutes is adequate for a 240mm AIO to reach thermal saturation. Let's see what sort of Core temperatures you get.

CT 😎
 

jdidds

Reputable
Mar 17, 2019
36
1
4,535
jdidds,

Your ambient temperature is within 1°C of normal.

Since the benchmark you used is now an unknown variable, if you're interested in seeing your rig's thermal performance using a valid 100%TDP workload, then your next step should be to click on the link I provided in my post above, download Prime95 version 26.6 and run Small FFT's.

10 minutes is adequate for a 240mm AIO to reach thermal saturation. Let's see what sort of Core temperatures you get.

CT 😎

I'll get on to that. Maybe Wednesday before I can try it as I have a busy work schedule the next days. I'll post here with the results :)