Lenovo firmware archive of 6.05 MB labelled for the ThinkPad X1 Yoga Gen 3, though the name carries no board number, revision or chip size. Open the archive to check what it contains and whether it is a full SPI dump or an update package. When writing with a programmer, save the original contents first, since ThinkPads keep serial and security data in flash. Match the image size to the chip on your board, and confirm the board number on the PCB fits this model.
The button opens the matching file on RM Schematics, or a source page if it is not catalogued there yet. The original attachment is from @fixtronix. Enginerys does not host this file.
How to open a .rar file
Compressed archive — the usual wrapper for a schematic + boardview pair or a BIOS + EC set.
Back up your own chip before writing any dump, and match the full board number and revision. Flashing guide →