What should I do after having flashed a BIOS?

[mkdj]

Dear all,

I did my first laptop repair related to a BIOS issue. Laptop is a Lenovo ThinkPad T480, and was not booting. With my brand new programmer, I did a back-up of the current not working BIOS, erased the BIOS chip, and flashed this dump: https://www.badcaps.net/forum/troubl...83#post3686683

Now the laptop works fine, I can access BIOS and boot on a USB drive. But I read stuff about DMI, and information I should transfer from my old non-working BIOS dump to the new one.

Question #1 : Can someone tell me what should I do after having flashed a BIOS file like I did? You can also provide me a link to a trusted tutorial.

Besides, I supposed that, as I have flashed a BIOS file, I have lost some info, for instance related to the serial number of the laptop. But when I check on the BIOS of the newly working BIOS, I do have the correct serial number.

Question #2 : Can someone explains why I still have the right serial number on the BIOS after having flashed a new file found online, unrelated to my previous BIOS?


Thank you for reading,
Regards,
mkdj

[m1ch43lzm]

Question #2 : Can someone explains why I still have the right serial number on the BIOS after having flashed a new file found online, unrelated to my previous BIOS?

Lenovo ThinkPads store the serial number/MTM/model name/BIOS password in the EC (embedded controller), on other brands/models (example: Lenovo Ideapad/Legion/LOQ/Yoga/ThinkBook) that info along the Win license key is stored on the main BIOS, what we do is transfer that data from the corrupt BIOS to the new one
Maybe the Win license key is in your original (corrupt) BIOS, the new one you flashed doesn't have a Win license key, search with hex editor for 01 00 00 00 00 00 00 00 01 00 00 00 00 00 00 00 1D 00 00 00 (hex)

As long as you flashed a BIOS with a clean ME region, you should have no issues afterwards

[mkdj]

Dear m1ch43lzm,

Thank you very much for your explanation, it does make a lot of sense to me.

I searched the hex chain you wrote in both my corrupted and new BIOS, and I do see what looks like a Win license key in both files, just after the hex chain. I do have slight differences around the license key, as shown on the pictures below. I am talking about the "I" which is ß in the new BIOS, but most importantly about the 3305156851758 which is 3305162513371 in the new one.

When transferring the license key to the new BIOS, should I also transfer that data that is slightly different?


Regards,
mkdj

[m1ch43lzm]

I downloaded the BIOS you linked, copy the entire block from 88F110-88F22F from your corrupt BIOS, paste overwrite on the new BIOS (make sure the file size doesn't change), the other bytes may be a checksum or something else

The 330516... value is displayed in BIOS setup under "Preinstalled OS license"/OA3 key ID or something like that
On Windows, open command prompt and run the following command:

wmic path softwarelicensingservice get OA3xOriginalProductKey

It should return the Win key embedded in BIOS, like this:

OA3xOriginalProductKey
XXXXX-YYYYY-ZZZZZ-AAAAA-BBBBB