Sorry to hear that the UEFI solution did not help. My expertise is limited here. Wait for any suggestion from Eric or anyone else for another 1 day. Here is what I could think of:
Try upgrading the UEFI to latest 5.2 using the following weblink:
http://ftp.hp.com/pub/softpaq/sp62001-62500/sp62194.exe
Also download the F22 BIOS from the following weblink:
ftp://ftp.hp.com/pub/softpaq/sp57501-58000/sp57754.exe
Firmware can be installed manually; must have BIN file and signature file. This should only be done in extremely rare circumstances
Unzip this BIOS update and store it in a flash drive. Copy the HpBiosUpdate32.sig file from BIOS update folder to the root folder of the flash drive. Also copy 68CVD.BIN file from ROMPAQ folder to the root folder of the flash drive.
Keep the flashdrive connected, go to UEFI...select firmware management...select New...and navigate to the flash drive. This should pickup the BIOS update from the flash drive.