Why Intel PL1 drops in tigerlake?

[Islam Ghunym]

I have my hands on an HP laptop with tigerlake Intel I5-1135G7.

 

Stock specified power limits are 17W for PL1 and 35W for PL2.

 

Over time PL1 is dropping gradually to 10W (minimum value in the range 10-17). This behaviour is making the CPU performance trash.

 

The CPU is not overheating at all....

What is confusing is that PL2 never changes unless the CPU hit 95° then PL2 drops a bit to 28W untill the short duration ends, but then PL1 appears as 15W then the PL1 limit drop to 10 gradually over about a minute making the performance crap.....

I thought maybe VRM is overheating, but then why going from idle to load seems to have no problems with staying at 35W untill short duration ends.... This could mean that VRM are not overheating, but something else is happening.

 

Any idea?

[unclewebb]

Have you tried removing the DPTF driver? This can help some power limit throttling issues. 

 

https://bradshacks.com/disable-dptf/

 

If the VRM was overheating, ThrottleStop would report this as VR THERMAL in the Limit Reasons window. If you do not see that then it is probably not the voltage regulators causing the problem. 

 

Dell likes to lower the PL1 power limit well below the rated TDP. It looks like HP is doing something similar. As you have discovered, this kills performance and there might not be any simple solution.