Intel Core i9-9880H Undervolt - Observations and Questions

[SAMyMAS]

Hello unclewebb,

ThinkPad P1 Gen 2

Would it be possible to advise/point me on the best optimal configuration of ThrotleStop. The laptop is not used for gaming. It has been cleaned and re-pasted. It has not any issues prior/after ThrottleStop using, the Limits shows GPU high temperature BDPROCHOT, EDP OTHER and CPU TVB. I do not know if it is normal/acceptable having them.

Please find the enclosed log file along with the screenshots after TS Bench and Cinebench cpu (multicore test throttling).

Thank you.

 

[unclewebb]

Try clearing the BD PROCHOT box on the main ThrottleStop screen and clear the Thermal Velocity Boost box in the FIVR window.

I prefer to set IccMax for both the core and the cache to the max, 255.75.

The big problem that I see in the log file is PL1 power limit throttling when power consumption is only 20W. That is significantly less than the 45W TDP power rating for the 9880H.

Intel® Core™ i9-9880H Processor (16M Cache, up to 4.80 GHz) Product Specifications

Intel® Core™ i9-9880H Processor (16M Cache, up to 4.80 GHz) quick reference guide including specifications, features, pricing, compatibility, design documentation, ordering codes, spec codes and more.

ark.intel.com

To try and fix this problem, check the MMIO Lock box which is near the top right corner of the TPL window. After you make all of those recommended changes, create a new log file and attach that to your next post.

 

[SAMyMAS]

Thank you @unclewebb for your prompt reply and the recommendations.

The changes are done and the log is attached. CPU at 100% almost is equal to Max 93C.

 

[unclewebb]

CPU at 100% almost is equal to Max 93C

Checking the MMIO Lock box has cured the power limit throttling problem.

It has been cleaned and re-pasted

What thermal paste did you use? MX-4 and many other popular thermal pastes designed for desktop computers can quickly fail when applied to a mobile CPU. Consider buying some Honeywell PTM7950. Most users report much better long term results when using Honeywell PTM7950. This helps eliminate any thermal paste pump out at high temperatures.

The 9880H is a powerful CPU when it is properly cooled and the power limits are increased. Without proper cooling, consider lowering the long term PL1 power limit to 60W or 55W. That is about all your cooling can handle at the moment. You could also reduce PL2 to 80W or 90W and reduce the turbo time limit to about 8 seconds.

Lenovo is using a PROCHOT Offset value of 8 which tells the CPU to begin thermal throttling at 92°C instead of the full Intel recommended value which is 100°C. Open the Options window and have a look on the right side for this setting. If you do not see a yellow lock icon near this setting, you can lower the PROCHOT Offset value to raise the thermal throttling temperature. An Offset value of 3 will tell the CPU to start throttling at 97°C which can be a slightly more aggressive compromise. Some people prefer not to change this setting.

 

[SAMyMAS]

Thank you @unclewebb for your detailed reply.

Yes, it was the MX-4. I will try the Honeywell PTM7950 thermal pad and revert back, incase anyone else is looking for the same CPU/laptop profile/configuration solution. In the meantime I applied the settings as per your recommendations (except for changing the PROCHOT Offset value). I can live with it for now and this can be considered solved.

The changes have impact but not very much the temperature reaches around 93C.

With your analyses/insights, it is apparent that this laptop is struggling between power/temperature throttling.

You have been a great help.

Have a good day.

 

[unclewebb]

this laptop is struggling between power/temperature throttling

This struggle happens in many, many laptops. Replacing the MX-4 should help you get more full load performance out of your laptop.

The changes have impact but not very much

If you want better temperatures you can lower the power limits some more. The 9880H has a 45W TDP rating. At default settings, many manufacturers set the PL1 turbo power limit equal to the 45W TDP rating. This can help reduce temperatures at the expense of reduced performance. You need proper thermal paste and an adequate heatsink to get maximum performance out of a 9880H.

When you run lots of high temperature stress tests with MX-4, the thermal paste will degrade or get pumped out and day by day, the CPU temperatures will continue to get worse. Hopefully you can come back here and share your results after installing Honeywell PTM7950.

 

[SAMyMAS]

Hopefully you can come back here and share your results after installing Honeywell PTM7950.

The PTM7950 has definitely improved performance. Compared to the benchmarks, it's skyrocketed from 2726 to 3200 in ETU and from 385 to 555 in Cinebench respectively. The temperature/power ratio is incrementally better too, ~60W to >65W see screenshot (log enclosed). But the best thing is that the performance has not deteriorated yet, unlike the MX-4, .

When you run lots of high temperature stress tests with MX-4, the thermal paste will degrade or get pumped out

as you kindly advised.

Thank you @unclewebb