[Request] Unlock undervolting on Acer Predator Helios 16 PH61-71


I would like to mod the Insyde Bios of my Acer Predator Helios 16 PH61-71 in order to unlock undervolting for its 13900HX CPU.

I am fairly new to this so I don’t know how to start, any help would be appreciated.

It uses Intel ME 16.1, I was only able to find CSME Tools for up to 16.0.

The Bios can be downloaded here:


Extracted (ran the exe and found the folder in c:\windows\temp)

Thank you for your help.

Regards. (691.5 KB)

A new version is shared, Intel FPTW.exe for 16.1. fptw.efi.


Thank you. I was able to dump the bios with this tool. Following this guide Undervolting 2020 Dell Laptops like the Vostro 7500 and More Tips to Improve Thermals, Battery Life, and Speed - Brendan Greenley

I was able to unlock overclocking, but not undervolting. There is also an offset 0x381 in CpuSetup that is called “UndvervoltLock” but setting it to 0x0 does not disable undervolt protection. I can only set positive offsets in Intel XTU. Throttlestop allows negative values, but they do not stick.


same problem here with my helios 16. is there any news here in the meantime?

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Hi ColinMacLaren …Have you made any progress here in the meantime? setting the Undervoltlock to 0x0 has no effect on me either

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Hi @Klaus3DDA, not really. I even got my bios unlocked, but all the hidden options, including undervolting manually in the in the hidden bios, don’t do anything. The undervolting lock has to be on the CPU’s microcode level. However, I had some success with loadline undervolting. That’s offset 0x132 in variable CpuSetup for Core AC loadline. The value is in 10s of mOhm. So setting it to 0x64 would be 1.000mv. The default value is 1.700 mOhm. You can monitor it in HWInfo under CPU.

However, the loadline value is volatile and has to be set every time before booting the OS. I put an EFI Shell in the hidden FAT32-Boot partition and use the startup.sh Script to first set the loadline value and then chainload Windows. This does work, but it required disabling secure boot, which is required by some AntiCheat-Engines like EA and Valorant.

Going too low will result in higher clock rates, but actually lower benchmark scores. 1.000-1200mOhms is a good bet.

  • Hello Sir, I have also unlocked the bios of my computer, but after the computer is restarted, the bios will reset ac loadline every time, I want some help, can you provide the content of configuring efi shell process and bash script? Thank you
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I’m Chinese, My English is not very good, please forgive me,and now Chinese players can’t solve the problem that the computer can’t lower the voltage. I hope some friends can release the unlock file, thank you.

Any new news? I just got this system and been unsuccessful.
Any help would be appreciated.
Thank you.

No, only some Loadline Undervolting and unlocking Overclocking in Throttlestop.

How do i unlock overclocking in throttlestop?
Do i mod my bios?
Im on 1.16 insyde bios right now.

I specifically want to underclock my cpu and overclock my gpu. But overclocking/underclocking is locked in the throttlestop.

Has anyone figured the undervolt out? i can have my bios unlocked at any moment, but there is no way to undervolt from in the bios,