Cannot undervolt with either ThrottleStop or Intel XTU

[25*GenMajWebelo]

I'm using 'retrain' as a generic term. As for how the BIOS updates hardware information and applies these settings to the Windows Boot Loader is a bit more indepth.

Test it.

If you want to understand what is happening, you will need a deeper dive into Intel microcode, how bios hold specific updates to the microcode, and how they are applied through EFI to the booting operating system.

TLR - And I'm being very vague here to make this digestible for average readers.

The OS's UEFI load must be coordinated with the microcode/firmware changes and settings in the BIOS. If not, the BIOS microcode is used, and Windows is locked from loading additional microcode or managing the CPU from inside Windows. By resetting factory defaults, on the next boot, the BIOS will present the Windows UEFI boot with the new information so that it may coordinated and store it in the bootloader.

When this is out of sync, the BIOS microcode and settings are absolute, thus preventing Windows loading the full microcode in 'genuine' - and Windows along with all software on Windows is prevent from adjusting, changing, or managing CPU features as they are locked in the basic BIOS microcode that first loaded.

I don't mind explaining things or providing basic references; and I am always open to being wrong or mistaken.

The best references would be specifically in the: Windows UEFI firmware update platform, sections on the Microsoft site from: https://docs.microsoft.com/en-us/windows-hardware/drivers/bringup/boot-and-uefi

(Intel also provides information on how microcode is loaded though bios/firmware updates with the expectation of a more adaptive/performant version to be loaded by the operating system.

Just trying to help.

So, it sounds like you two know what you're talking about so I would ask if you can dumb it down for me?

My new laptop arrived with the voltage locked and I have been reading all the info I can find about Plundervolt workarounds. I asked Dell ProSupport if I can flash downgrade my BIOS and they said it would NOT void my warranty; however, I am still hesitant to do this. If there is a way I can have full access to my CPU without flashing, I would be more comfortable.

Dell Precision 7740
i9-9980hk
Hynix 64GB @2666
Quadro RTX 4000

I have disabled SGX and was able to restore settings so that my CPU can break 2.4 GHz (all 8 cores are running up to 4.9 GHz now) but with the RTX I'm going to set my desk on fire, as voltage is still locked in XTU.
In UEFI my Restore Settings options are:
1) BIOS Defaults
2) Factory Settings
3) Last Known Good Settings
4) Custom User Settings

I've tried 1 and 2 but still cannot access voltage. If you are able to provide a step-by-step for me, I would be most appreciative.
Thank you in advance.

 

[michaelkourlas]

For example there is a Dell G7 brand of notebook, and the 'rumor' is that all later BIOS updates lock ThrottleStop and XTU from undervolting. However, the functionality NEVER changed. This isn't true, as the latest June 2020 1.13 BIOS works just fine with XTU and ThrottleStop.

The reason changing to an older BIOS 'seems' to work, is that users rollback will do a 'Load System Defaults' when rolling back - or the rollback process of the BIOS itself runs the retrain boot feature. This also requires the current Windows EFI boot be selected as the retrain/boot information is added to that boot loader's EFI. (So if you have Dual Windows Installs for testing, 'Load System Defaults' when booting (after the Windows Boot Manager Selection Screen)

The option is usually 'Load System Defaults' -as BIOS defaults just loads settings but does not force any hardware retraining. If the BIOS doesn't seem to retrain, there is often a Power Button combination (Hold Power Button 45 Seconds) that will force the retraining - see OEM manuals. Ultimately, the user can also pull the CMOS and/or system battery for 30 seconds, this will force a full RAM and CPU/Microcode/Boot/Firmware/UEFI retraining.

Apologies for resurrecting this thread, but I just wanted to add to the historical record here. I have an XPS 9570 running Windows 10 20H2 with BIOS 1.18.1. Previously, ThrottleStop wouldn't let me undervolt as the FIVR Control options were disabled. After resetting my BIOS to "Factory Defaults", the options are no longer disabled. Thanks very much for the tip!

 

[Minarch]

Here is somthing that would work: