Clean ME for 820-2850 so I can change SN for a MB replacement

[Paul Daniels]

Hello all, definitely calling in a plz-bro on this.

I've got an A1286 with an i7 2.66GHz mainboard that I have to replace for a client and I want to migrate the SN, unfortunately none of the clean-ME region BIOS images for the 820-2850 seemed to work for me ( usually 165, 3437 and similar ones aren't a drama, so I'm missing something here ).

SN: C02JX0XKF1G3

Is there a service anyone here is offering for creating such a BIOS image?

 

[2informaticos]

820-2850 Bioses Clean ME.zip

drive.google.com

Only need to change SSN and fix Fsys checksum.

Do you have Medusa programmer?
Be aware, it doesn't clean ME region for Ibex Peak PCH.

 

[Paul Daniels]

Thanks. I don't have the Medusa. I still do it the long way, removing the chip, reflashing and resoldering; which at least works for all the boards.

 

[Paul Daniels]

Right, this is where I'm runnning in to an issue. The supplied BIOS has room for 11 character SN, where's the SN I have for this machine is 12 characters; so where do I factor in the extra byte? I can expand the whole section of the file and removing two of the zero-bytes immediately following the ssn section (2 bytes, one for the SN, another for the 4-byte ending between .hwc and .son ), or overwrite one of the bytes either prefixing or suffixing.


If I was to guess, I'd almost say pushing the section in to the zero byte area following would be the correct functional option.

Anyone experienced this?

 

[2informaticos]

Your SN seems to be for 2012 machine...

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[Paul Daniels]

That makes things all the more curious. I'm wondering if the bottom plate that was fitted is in fact the incorrect one for the chassis/machine that was supplied. Unfortunately the mainboard was dead (PCH) as such I was not able to boot to confirm the SN.

Just realised now I can take the chip from the dead mainboard (BIOS) read it, and check internally.

For the record, the adding of two bytes and removing two of the zero bytes did result in a readable UEFI structure and was able to generate a correct checksum.

 

[Paul Daniels]

Your SN seems to be for 2012 machine..

... and that was the penny-drop moment. After I pulled the BIOS off the dead board, checked its SN, lo behold, it's a W8012... 11 byte SN. Explains a lot of things.

Thank you. This task is now complete.