Hi guys, hope that someone can help me.

I have a Surface pro 3 which became nearly a brick after a failed update (only surface logo appears and no boot from usb)
i suspect it's a uefi issue so i decided to take it apart and try to flash the uefi through a raspberry pi, reading the chip to make a backup was flawless but trying to find a good uefi image is driving me crazy.
By following a guide online i found out that the surface pro 3 driver pack from microsoft contains the uefi firmware in a capsule format, used uefitool to remove the header and tried to flash it but flashrom tells me that the file size do not match, dumped firmware is 16777216 bytes while the extracted one is 16777260 bytes. I don't know what these 44 extra bytes are!
Trying to find a compatible dump online is nearly impossible, the only one i found was for a different motherboard serial (but size was correct) and didn't work as all i got was a black screen.

Maybe someone have a working flash dump to share?

Thank you all and sorry for my bad english.