Corrupted/Interrupted Bios Update Lenovo Legion S7 15ACH6

[Thomas Dunlap]

Hello,

I have a Lenovo Legion S7 15ACH6 that was interrupted during a BIOS update and is now bricked. Symptoms: fans spin, RGB keyboard lights up, but no display/POST.

The BIOS chip is a Gigadevice GD25LR128. I’m using a CH341A with a 1.8 V adapter. In AsProgrammer I selected GD25Q128 (since GD25LR128 isn’t listed) and successfully made a dump (BiosDump2_pf3eg12j.rar).

My understanding is that I’ll need a known good BIOS dump for this exact model, ideally matched to my laptop’s serial number (PF3EG12J), and that the Windows license key/serial should also be preserved.

Can anyone guide me through the proper process of rebuilding or flashing the BIOS for this machine?

Thanks in advance!

[m1ch43lzm]

BIOS extracted from Lenovo website, DMI inserted (serial/win key)

Legion S7-15ACH6 Laptop (Lenovo) - Type 82K8
S/N PF3EG12J
MTM 82K80083US
BIOS ver. HACN46WW
DMI 62B000-62CFFF

[m1ch43lzm]

BIOS extracted from Lenovo website, DMI inserted (serial/win key)

Legion S7-15ACH6 Laptop (Lenovo) - Type 82K8
S/N PF3EG12J
MTM 82K80083US
BIOS ver. HACN46WW
DMI 62B000-62CFFF

[Thomas Dunlap]

m1ch43lzm, thank you for all the help! I wanted to learn more about the process that you undertook to get the end result of the proper bios for my machine. Can you point me to resources I could look at to learn more. Thanks again!

[m1ch43lzm]

How to extract BIOS update from Lenovo (Phoenix BIOS)
https://www.badcaps.net/forum/troubl...oenix-tdk-bios

And check post 46 for an easier way of doing it https://www.badcaps.net/forum/troubl...51#post3733751

For the DMI (serial/model/MTM), and Win key, it's encrypted on this model, search for LENV with hex editor, it will appear 2 times, from the first LENV (at 62B000h) select 2000h, that covers both LENV blocks, copy/paste write that to the clean extracted BIOS, make sure you don't add extra bytes to the file

I noted the range you have to copy from the old BIOS to the new one, 62B000-62CFFF