According to my understandings, the firmware is the actual embedded code loaded onto the chips, the driver is the software .SYS or .DLL that handles the communication between the x86 system and the external chips. Thus, the firmware version must match the driver version, otherwise the device won't work.
I had a guess that in Device Manager, it is the driver version shown. And in the boot-up UEFI screen (press power and vol+ to power on the device, but not hold too long), it is the actual firmware version shown.
When you roll-back driver in Device Manager, the firmware is not touched. According to the official surface book update history page:
- Firmware updates cannot be uninstalled or reverted to an earlier version.
Can you please check both the driver version and the firmware version? See if they match?
Can somebody from MS confirm (or correct) my guesses?