So my beloved HP Z620 Workstation Monster has just suffered a BIOS update failure.
It seems that this is a common issue with running the update from within Windows 10.
Following various post including this one seem to have not worked: https://h30434.www3.hp.com/t5/Business-PCs-Workstations-and-Point-of-Sale-Systems/Crisis-Recovery-Jumper-Z620-Z420-Z820-Revealed/td-p/6658619?lightbox-message-images-6658619=179776i02BEED432C66A811
$110 later, new board on the way. Seems that whatever happened has super broken it to the point even the recovery ROM does not function.
Removing the RAM triggers an error status with beeps and red lights meaning it doesn’t appear to be completely dead.
Wow…..a few months later, as a suggestion, a rom programmer will have been far way chiper, with a clamp over bios chip you should have been able to reflash it with original bios or whatever version without issue.
Maybe on an older BIOS system but this being UEFI I don’t know what kinds of security junk is included in that code!
Tracking down a brand new sealed board on eBay was far less hassle in the long run. Machine is running a treat now with the latest firmware. Never installing via Windows again!