Power On Password

Specifically the troubleshooting guide here: http://h20566.www2.hp.com/hpsc/doc/public/display?docId=emr_na-c01516072  explains how to reset the BIOS passwords.

Resetting the Password with the Reset Jumper

To disable the power-on or setup password features, or to clear the power-on or setup passwords,
complete the following steps:

1. Shut down the operating system properly, then turn off the computer and any external devices, and disconnect the power cord from the power outlet.
2. With the power cord disconnected, press the power button again to drain the system of any residual power.
3. Remove the computer cover or access panel.
4. Locate the header and jumper.  NOTE: The password jumper is green so that it can be easily identified. For assistance locating the password jumper and other system board components, see the Illustrated Parts & Service Map (IPSM) for that particular system. The IPSM can be downloaded from http://www.hp.com/support.
5. Remove the jumper from pins 1 and 2. Place the jumper on either pin 1 or 2, but not both, so that it does not get lost.
6. Replace the computer cover or access panel.
7. Reconnect the external equipment.
8. Plug in the computer and turn on power. Allow the operating system to start. This clears the current passwords and disables the password features.
9. To establish new passwords, repeat steps 1 through 4, replace the password jumper on pins 1 and 2, then repeat steps 6 through 8. Establish the new passwords in Computer Setup. Refer to the Computer Setup (F10) Utility Guide for Computer Setup instructions.

Clearing and Resetting the CMOS

The computer’s configuration memory (CMOS) stores information about the computer’s configuration.  The CMOS button resets CMOS but does not clear the power-on and setup passwords. Clearing CMOS will clear the Active Management Technology (AMT) settings in the Management Engine BIOS Extension (MEBx), including the password. The password will default to “admin” and will need to be reset. The AMT settings will also need to be reset. To access the MEBx, press Ctrl+P during POST.

1. Turn off the computer and any external devices, and disconnect the power cord from the power outlet.
2. Disconnect the keyboard, monitor, and any other external equipment connected to the computer.
3. Remove the computer cover or access panel. CAUTION: Pushing the CMOS button will reset CMOS values to factory defaults. It is important to back up the computer CMOS settings before resetting them in case they are needed later. Back up is easily done through Computer Setup. See the Computer Setup (F10) Utility Guide for information on backing up the CMOS settings.
4. Locate, press, and hold the CMOS button in for five seconds.  NOTE: Make sure you have disconnected the AC power cord from the wall outlet. The CMOS button will not clear CMOS if the power cord is connected.  NOTE: For assistance locating the CMOS button and other system board components, see the Illustrated Parts & Service Map (IPSM) for that particular system.
5. Replace the computer cover or access panel.
6. Reconnect the external devices.
7. Plug in the computer and turn on power.

NOTE: You will receive POST error messages after clearing CMOS and rebooting advising you that configuration changes have occurred. Use Computer Setup to reset any special system setups along with the date and time. For instructions on Computer Setup, see the Computer Setup (F10) Utility Guide.

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