EliteDesk 800 G2 Motherboard error codes

[OldDave13]

I made the cardinal mistake of working on my PC after 10pm. After foolishly removing the pci video card without unplugging the power I now get the error code of 5 long beeps and 2 short beeps that indicates I should clear the CMOS. I've followed all the steps online, unplugging the power, pressing the CMOS Clear button for 10+ sec, holding the power button for 120+ sec, removing the cmos battery, holding the buttons again. Any secrets to this or do I just need to replace the motherboard? 

Thanks in advance!

[Paul_Tikkanen]

Hi:

According to chapter 7, page 116 of the service manual, your PC's BIOS has a problem.

Maintenance and Service Guide HP EliteDesk 800 G2 TWR Business PC

System board:  5.2   The embedded controller cannot find valid firmware.

Try making a bootable BIOS recovery drive with the latest BIOS update.

Driver - HP EliteDesk 800 G2 Tower PC | HP® Customer Support

I have zipped up and attached the instructions below, for the various ways to update the BIOS.

Read the section under this heading...

HP BIOS Update and Recovery (HPBIOSUPDREC) BIOS Flashing

[OldDave13]

Thank you Paul for the specs and guidance.

Unfortunately I cannot get past the 5 long beeps and 2 short beeps to get to the bios menu or to boot from a USB. I've let it sit for a couple of hours with the BIOS battery removed and it is still beeping that error pattern. Do you have any additional thoughts?

[Paul_Tikkanen]

You're very welcome.

I gave you the wrong section to read.  You have to read the last section.

Unfortunately, I don't have any first-hand experience with recovering the BIOS when you can't do anything.

However, it is my understanding that if you create the BIOS recovery drive and plug the flash drive into the USB port and power on the PC, the PC is supposed to find the BIOS files on the flash drive and the recovery process would begin.

Crisis Recovery Mode

In the event of a failed BIOS update (for example if power is lost while updating), the System BIOS may become corrupted.

Crisis Recovery Mode detects this condition and will automatically attempt to recover to a known good state.

Some advanced systems have the ability to recover without user intervention - an error response during boot up showing 2 red and then 4 white blinks on the power LED indicates this mode. After restoring the BIOS image, the system will reboot normally.

If this feature is not present on your model, the recovery process will search the hard drive and any USB media sources for a compatible binary image.  

The original factory image will have a suitable BIOS binary for automatic recovery without user intervention.

Otherwise, the binary (.bin) file in the HPBIOSUPDREC folder should be copied to the "Hewlett-Packard\BIOS\current" or "EFI\HP\BIOS\current" folder of the desired storage device in a FAT or FAT32 partition, and the system powered on.

Once the binary image is located, the BIOS will display a recovery screen and will start the recovery process.

Do not power off the system until recovery is complete.

Whenever HPBIOSUPDREC is used to update the BIOS, the utility will automatically populate the recovery file in the correct location should the Tools partition or \EFI file path exist.

This process can be used to configure for automatic recovery a system which has had the original hard drive image replaced or reinstalled with system software recovery media.

Sometimes there are restrictions on which BIOS versions are allowed to be installed on a platform.

If the BIOS that was on the system had restrictions, then only allowable BIOS versions may be used for recovery.