Dell OptiPlex 9020MT firmware dump labelled 4M, exactly 4.00 MB, intended for the smaller of the two SPI flash chips used on this mini-tower system. It pairs with the 8 MB image for the second chip, and both should be written for a complete firmware set. Before programming, dump and keep a copy of the existing chip, since it holds board-specific data such as the service tag. Confirm the chip on the board is a 32 Mbit part, as a file of the wrong size will not fit the device.
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 @laptopbios21. Enginerys does not host this file.
How to open a .bin file
A raw, byte-for-byte image of a flash chip: the main BIOS / UEFI, the embedded-controller (EC) firmware, or both.
Back up your own chip before writing any dump, and match the full board number and revision. Flashing guide →