The HP EliteBook 840 G6 uses a security chip that stores the BIOS password in non-volatile memory. This means removing the CMOS battery (the coin cell battery) will not work. The password will persist even if the board loses all power.

Here are the three real ways this is handled:

If you are reading this, you have likely run into one of the most frustrating hurdles in IT maintenance: a locked BIOS. You turn on an HP EliteBook 840 G6, and before it even boots to Windows, it demands a password you don't have.

For modern laptops, the days of simply removing a CMOS battery are long gone. HP’s security architecture on the EliteBook 840 G6 (and the entire G6 series) is robust. However, for technicians and system administrators, there is a specific method involving a BIOS Password Reset Utility that can resolve this without replacing the motherboard.

In this guide, we discuss the "Repack" utility method, how it works, and the steps to unlock your device.

This is the method most technicians search for. HP provides a specialized binary file (SMC.BIN) to authorized service centers.

On the HP EliteBook 840 G6, the BIOS chip (Winbond 25Q256JVEQ) is located near the memory slots and the CMOS battery. You do not need to physically clip a programmer to it if you use the software-based SPI brute force contained in the repack. However, if the repack fails, you will need a CH341A programmer and SOIC8 clip.