Eurocom X4C Black screen after enabling secureboot and installing custom keys

Hi

I have a Eurocom X4C (Clevo P751TM1-G) that i bought a few month to replace an Eurocom P5 Pro that died.

I had to enable SecureBoot with custom keys (PK/KEK/DB) for my linux work OS.
I entered the BIOS/UEFI , enabled those options and configured as well the User password.
After reboot i only get a black screen.

After some times i realized that the system still somehow tries to boot and some clevo related options like FN+1 enables the fans... but with a permanent black screen on main and external panel.

There is a really similar case on this link for an hp laptop .

It seems that changing BIOS parameter mangle some other parameters on the SPI BIOS Chip .

I asked Eurocom support if i can eventually try to reflash externally the BIOS without losing the Waranty as i have an SPI flasher .

If anybody have any advice to solve this problem or similar case would be really nice to know about it. I will update this post based on their support input and once the situation is resolved.

Best Regards

 

Getting a full file rather than an update can be tricky.

 

why ?

Yesterday support sent me the update zip that they are using. for updating from wwindows there is a file BIOS.ROM in it of 8Mb, i opened it with UEFITOOL and it looks like a legit BIOS DUMP.
However all their laptop i had so far had 2 chip, a 8 MB an a 4MB, not sure about this one

However on the phone another technician told me that this approach cant be done as the File is encrypted and edited on the fly before being flashed ...
I played a bit with coreboot on my server board and several lenovo laptops an never heard of that.

I m just hoping that i did not enter an infinite administrative maze that will last for weeks.
So far the technician i had where really nice so i hope for the best

Edit : I guess flashing is not possible due to Bootguard protection from Intel actually ;(

 

Im dealing with a really nice team from Eurocom. I provided my keys to the technician that managed to reproduce the issue and bricked their test laptop too ;(

The easiest solution is to replace the motherboard.
The keys where created with the standard procedure explained in this Arch Linux Wiki

Until Eurocom or Clevo provide an update to fix this issue, i think it would not be recommended to try custom secureboot keys for anybody using this family of laptops.

 

Thanks for sharing, good to be aware of.