In the first post you said,
so much for that theory!
This is a low power U series CPU. Intel specifically designed these things to throttle. Your CPU is performing exactly as Intel intended.
If you look at Limit Reasons, PL1 is red. When this happens, it is normal for EDP OTHER in the RING column to also go red at the exact same time. Ignore EDP OTHER. It is PL1 causing the throttling. If you look at the main ThrottleStop screen it shows to the right of the PKG (Package) Power button that the CPU is presently running at 15.0 Watts. The TDP for the Core i5-8265U is exactly 15 Watts.
quick reference guide including specifications, features, pricing, compatibility, design documentation, ordering codes, spec codes and more.
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Intel recommends that manufacturers set the long term turbo power limit equal to the TDP so it looks like HP has followed that advice exactly and has set this to 15 Watts. To try to work around this limitation, while Cinebench is running and your CPU is being throttled by this 15 Watt limit, click on the TPL button and open up the Turbo Power Limits window. You did not post a pic of this window like I asked, hint hint hint, so I will have to guess. The Turbo Boost Long Power Max is probably set to 15 Watts. If the Lock option is not checked, try increasing this value to 20. Click on OK and go back out to the main window and see if this has made any difference to your CPU speed or power consumption. Is PL1 still glowing red?
Your CPU is probably still throttling. There are actually multiple sets of turbo power limits that control Intel CPUs. The next thing to try is open up the FIVR window, and on the right hand side, you want to check the Disable and Lock Turbo Power Limits box. Before you check this box, go a little further to the right and you should see an Install button. Click on this button and follow the directions. It will tell you to download the RwDrv.zip file from Mega. Do this. Open up the zip file and copy the RwDrv.sys file into your ThrottleStop folder. Close the FIVR window and open it back up. If it finds that you installed that file in your ThrottleStop folder, the Install button will be gone. Now you can click on the Disable and Lock box and press OK and do some more testing.
Run Cinebench again. If this box is checked and the ThrottleStop Turbo Boost Long Power Max is set to 20 Watts and your CPU is still throttling to 15 Watts, that means you are screwed. At this point there is a third set of turbo power limits controlled by the EC. I have a hunch that HP uses this third set of power limits. There is no software available at the moment to go beyond this limit.
You can use ThrottleStop to under volt the CPU core and CPU cache but on U series CPUs, the benefit of this is limited. I will explain this further later. In the FIVR window you will need to undervolt the core and cache equally. I would start by using an undervolt of about -50 mV. Reducing the voltage will allow the CPU to run slightly faster before it starts throttling. No huge gains to be had but it also helps keep the temps down.
I would also clear the BD PROCHOT box on the main screen of ThrottleStop.
Have fun playing and post some more results. I rarely hear from HP owners. Always good to learn some new info about what is possible. The Lenovo laptops I have bought lately have unlocked turbo power limits so the results are much more impressive.
