1908 ME should be 8.1.2.1318, so you do have 1616 ME
Time for a new chip
(Be sure and come back and let me know what happens)
Takes 5 working days to arrive
The 8 pins come splayed out - have to carefully straighten them to verticle
Notch on plastic top end only goes one way
Must be all the way down both sides
PC off and PSU unplugged
After insert, reinitialize power, start a boot, then shut down and cmos reset.
Since you have issues with all but 1616, I would buy one chip 1908 and one 1616, but thats just me - heh
UPDATE:
After reading this mess again, I'm now thinking of possibility that you could have bad mobo/vidcard/PSU - maybe nothing wrong with bios (now). Boot cant do vidcard successfully and defaults to IGPU instead, then corrupts bios settings. (you had several mobo video red led)
This would explain why "Auto" works and PCIe doesnt - auto is either IGPU or PCIe, PCIe leaves no other option.
After booting a few times vidcard boot fails (cold boot) and bios falls back to IGPU..
Vidcard might be crapping out (2 monitors), power to card not sufficient, or card not all the way down due to case geometry, or bad slot.
Make sense?
You have GOT TO try another low level card with ONE monitor!
I am also not discounting the possibility of your PCIe soundcard wrecking things. Z77 mobo only like a few brands - with later bios. I had a list but I cant find it now.
So you actually had a two part problem:
Flakey vidcard causing IGPU default ("active") - thats why you wanted to try 1908
Bad bios flash made everything much worse.
However, a new chip will settle this part of the question once and for all.