For the HP EliteBook 840 G5 Go to product viewer dialog for this item.
The EliteBook 840 G5 uses a 1.8V low-voltage SPI flash chip . Most cheap programmers (CH341A default settings) output 3.3V or 5V, which will instantly destroy the chip. You must use a 1.8V adapter or a dedicated programmer like the CH341A Black Edition with 1.8V switch . hp elitebook 840 g5 bios bin file