P51 I7-7820HQ thermal trottling

Hi all,

I recently purchased a P51 laptop with a I7-7820HQ CPU and Nvidia M2200 GPU.
What I noticed, almost immediately, is that the CPU fans frequently reach high RPMs (~4500) even when loaded only for a few seconds during application launch.

Testing with Intel Extreme Tuning Utility uncovered almost immediate thermal throttling, only a few seconds after a CPU stress test is launched. Expected core frequency of 3.5 GHz is reached only briefly and after this it is throttled to 2.7-3.0 GHz within 5 minutes of the test.

Since the system board was replaced recently, I guess there is a possibility of improperly installed cooling system, however, what causes additional concerns is a big temperature difference between the cores which is more than 20 degrees Celsius under 100 % load.
Except this, it seems that the air coming out of the laptop during the stress test is only slightly warm and significantly cooler than what I am used to on other laptops.

On the other side, Nvidia GPU seems to behave quite well under stress test (Furmark).

Except this, I also tried to run Intel Processor Diagnostic Tool but the test failed before reaching GPU stress test because of too high temperature with the following result:

Current Junction Temperature is 99C
Current Degrees Below Max 1C
Maximum Junction Temp Allowed 100C
Test Result - FAIL
Please check your Processor Thermal Solution
Temperature Monitor Stopped by User

I have uploaded the benchmark results here:

https://drive.google.com/drive/folders/1yHWbAZPLnXuW2TJTpuqJIE_RjxlSueLf

Can you please advise how to solve this and share your results with similar laptop configurations?

 

Repaste your notebook with high quality thermal interface material, such as kryonaut, ICDiamond or GC Gelid, then undervolt your CPU, after that your should be absolutely fine.

 

That is definitely something I plan to do, however, I am still concerned with > 25 degrees Celcius temperature difference between the CPU cores under maximum load, do you believe repasting will help with that?
My understanding is that the deviation should not be > 10 degrees Celsius.

 

Yes, a reseat and applying proper thermal tim should solve this issue. Fairly certain this is caused by insufficient amount of tim and/or bad mounting of the heatsink.

 

On these machines, Mylar sheets are used to shield the board against possible water intake. It's possible that the mylar sheet cutout for the cpu die is placed just slightly off center that it's actually sitting on the silicon instead of the substrate.

 

Didn't know that, possible. The system should somewhat be able to handle the 4700MQ ( I expect around 85ish C on stresstest on stock speeds with undervolt), so seeing 2.4ghz and 90+C has to be something that went wrong.

 

go here and input 01AV343, the heatsink isn't very beefy

https://support.lenovo.com/us/en/partslookup

 

EDIT; wow somehow thought i was in a different thread. Are you sure that's the heatsink?

The notebook seems to be shipped with either the 7920HQ or even a XEON CPU, I somehow cannot see how that heatsink is supposed to cool that.

 

I'm 100% sure that's the heatsink used for P51 and P50 ThinkPad models.


Highest CPU is x820HQ, and Xeon counterparts are not very different heat wise to the i7s.

I can't speak for the 1535M v6, only have th 1505M v6 which can turbo to 4 on single but is only 3.4 on multicore. So they don't produce much heat given you undervolt properly.

Illusion of potentially higher performance only on single core.

 

Ok, thank you guys, I will definitely do as you suggested.

 

what are you going to do?

 

I will check if there are issues with the heatsink installation as you suggested and repaste.

I was somewhat worried there could be issues with the thermal sensors, however, the core temperatures are almost the same when the CPU is idle, with a big deviation at 100 % load.

 

Deviation at load is normal and is sign of bad thermal conductivity.

Do you have onsite support?

 

Yes, with ~800 days remaining. Would you recommend that I use them, but provide own thermal paste?

 

yes