Elitebook 840 G5 latest bios 1.24.0

[Piotrtal]

I can't downgrade bios to the version 1.0.8 as it was the most stable version for me it don't heat up computer and have less bluescreen. How I can do this as downgrading from HP utilities is not possible. It's like it's protected.

It's private laptop and I would like run it on 1.0.8 version of bios.

[TzortzisG]

Hello Piotrtal.

Yes, BIOS 01.08.01 Rev.A dated Aug 14, 2019 is unfortunately the last version available before the "plundervolt mitigation" was forced upon 6th to 10th gen intel systems through firmware updates. Most of the times downgrading is not allowed due to "security reasons". It's locked. You have to do a force downgrade, which might also not work. To do a force downgrade, download the correct softpaq and create a USB recovery disk. Follow this guide: https://support.hp.com/us-en/document/ish_3932413-2337994-16 You need the last option (recovery with USB).

Good luck!

[Piotrtal]

It does not work. I receive message is blocked. How I can downgrade it as current bios is problematic in my case and I can't use peripheral like egpu? It's my personal laptop 

[TzortzisG]

You mean to say that the eGPU worked fine with the 4year old BIOS and doesn't work with the new one? This is weird.

If it's blocked, it's blocked. You can't do it. At least not in a normal way. This is the only way: https://h30434.www3.hp.com/t5/Notebook-Boot-and-Lockup/HP-G6-not-booting-after-BIOS-update/m-p/87009... External flashing of BIOS chip.