Desktop Boot and Lockup

This happened when I wanted to customize the BIOS settings. Specifically, the last change after which it didn't show screen and emitted 6 beeps is changing the PCI settings to "not download ROM". I did this because I had an SFP+ card that is always trying to boot from PXE and I wanted it to stop so I can boot my system.

Now, I can't even see a screen, bios post or anything, just the beeps. I tried resetting the CMOS with the button (reseating the graphics card, unplugging power cord, pressing for 5 sec, and replugging). Also, I have a password on the BIOS, would that affect any recovery procedure?

Just for the record, this post (bottom of post for z440/z640/z840 seems to *somewhat work*. That is, it boots, I see it is loading the BIOS from the USB (USB with light I can see it starting to flash at different speeds), and the workstation shuts down and turns ON on its own as described. HOWEVER, I didn't see any bios loaded on the screen, so now I don't know what is the state, and how I should proceed from here on.

PLEASE help, this is urgent matter as this is my main server that runs quiet a bit of services including backups, gitlab container, and other things.

Thanks in advance!