OldB0y, see my earlier post about doing in place upgrade. basically if you leave it connected to the internet, it will download the latest cumulative update. Fresh installation-blow-away-everything worked fine here, KB5016616 installed without issue. In place upgrade/install from USB, allowed successful install of windows (keeping programs etc.) but still failed on KB5016616 installation reboot stage.
ps. the in place upgrade whilst connected to the net, once it failed/i powered off, rolled back and reported the error "0xC1900101 0x30017" which according to here suggests:
"- Disable or remove all 3rd party antivirus or antispyware from your system. Disconnect all peripheral devices that are connected to the system, except for the mouse, keyboard and display.
- Contact your hardware vendor to obtain updated device drivers."
AV package was removed, no change. Given the machine is a win 7 upgrade, it has all the drivers that were originally in 7. I tried removing a ton of them, and still had no luck. Circling back, I don't think it is solely a BIOS/hardware issue, as I can fresh install and update fine (powered by a 720QM!)