HP EliteDesk 800 G4 MINI - No post/beeps after CMOS password reset

[llek1001]

Hello, I have recently got my hands on three HP EliteDesk 800 G4 MINIs from a local recycler, I tried booting them after I got them, they were without RAM, but I had some. I tried all of them, and they all booted to Windows 10 installs. I tried to access the BIOS but found out that it was password locked. I then followed this guide to reset the password [content removed]

After doing what the guide said I am completely unable to get any kind of output from the PCs, all three of them. This is what happens now, I plug in the mini pc, turn it on, it turns on for about a second, turns of, then turns of again for about 2 minutes and turns off. I am now unable to turn the pc on, if I press the power button, only a small green LED (HDD activity indicator) turns on while I hold the power button. If I hold it long enough, I can press it again to turn the PC on again, but it will just turn off after the 2 minutes.

Oh and I tried the VGA output as well as both display ports, and the plugged in keyboard remains dead.

I have tried to take out the wifi card, tried different RAM modules, and slots, and tried to take out the RAM completely, and this resulted in the normal beep and blink code for missing RAM.

I am now completely stuck and do now know what to do next, please, any help is much appreciated!

[RodrigoB]

Hey

Thank you for visiting the HP Support Community.

According to the Community's Rules of Participation:

4d. No posts shall include instructions/directions intended to bypass or subvert security mechanisms such as lock screens, BitLockers, BIOS lock, passwords, fingerprint/biometry scanners, PINs nor any other safety measures.

Therefore, this topic is being locked. If you would like help resetting the password on your product, please Contact HP support in your region. 

For cases related to BitLocker issues, please contact Microsoft Support.

Regards,

Stay safe.