Throttlestop - strange behaviour with HP 250 G7 (i5-8265U)

[osidovich]

ThrottleStop 8.74
Notebook HP 250 G7 (i5-8265U 1800Mhz), BIOS version F.23

Current settings (retrieved with HWiNFO64 v6.23-4080):

CPU Thermal Design Power (TDP): 15.0 W
CPU Power Limit 4 (PL4): 71.0 W
CPU Power Limits (Max): Power = Unlimited, Time = Unlimited
CPU Power Limit 1 - Long Duration: (91.25 W) (28.00 sec) [Unlocked]
CPU Power Limit 2 - Short Duration: (93.25 W) (2.44 ms) [Unlocked]
Configurable TDP Level 1 (Down): 10.00 W (Unlimited range), 800 MHz
Configurable TDP Level 2 (Up): 25.00 W (Unlimited range), 1800 MHz
Current Configurable TDP Level: Nominal [Unlocked]

MSR registers:

MSR_PKG_POWER_LIMIT (0x610) = 0x00428168 0x00DC8168

Memory locations:

0xFED159A0 = 0x00DD82DA
0xFED159A4 = 0x004282EA

Attached screenshots of TS config.



I've a lot of EDP OTHER in CORE/GPU/RING. Setting to max (255) IccMax of Core/Cache/GPU doesn't solve issue. Why?
Also I'm unable to reach 45W of TDP despite configuration.


I don't understand why PL1 and PL2 trigger at those TDP and TEMP values. Attached log.

With battery:

TDP throttle PL2 enters at ~30W and also at relatively lower temperatures. Why?

Weird rules are applied with AC!

TDP throttle PL2 enters at ~8W!

Could be a BIOS or hardware lock? I'm able to read/write NVRAM variables of CpuSetup with H2OUVE (uses an Insyde BIOS).

 

[unclewebb]

There are turbo power limits controlled by the EC that ThrottleStop and Intel XTU do not have access to. When a laptop manufacturer uses this third set of power limits, they can create throttling schemes that are difficult to overcome. HP is also the first manufacturer to start blocking under volting of Intel CPUs. Enthusiasts that like to play with various laptop settings should be shopping elsewhere.

The Lenovo convertible C930 that I tested also has an 8th Gen CPU. It did not have any power throttling issues. With the help of ThrottleStop, the only time it throttles is when it gets too hot and starts thermal throttling. That is how it should be. Sadly, many manufacturers are putting unreasonable limits on their laptops. This makes it impossible for consumers to make any sort of comparison. Performance is a mystery until you get a device home and have some time to do some thorough testing to see what is possible.

http://imgur.com/eo0J744

 

[osidovich]

There are turbo power limits controlled by the EC that ThrottleStop and Intel XTU do not have access to.

How can I found them? Reverse engineering the EC firmware? The BIOS?

HP is also the first manufacturer to start blocking under volting of Intel CPUs. Enthusiasts that like to play with various laptop settings should be shopping elsewhere.

It's my work laptop (I'm a software developer) so I can't change notebook. I can confirm that with my model and BIOS version I'm still able to undervolt CPU.

I've another question @unclewebb: it's normal that throttling scheme with battery is more performance oriented than throttling scheme with AC?

Using TS Bench (threads 8, size 256MB)

With AC, PL 2 enters at ~10W and when PL 2 is red PKG Power is between 8 and 15 W.

With battery, PL 2 enters at ~25W and when PL 2 is red PKG Power is between 15 and 30 W.

How can I better check this?