I have no idea what the SS12 part is, but i don't think its a vital part. I don't recall it from the last 2 nf7 based machines I built.

If possible try using other components to test it with ie different RAM, cpu, gfx card. Also try the ram in different slots, it sometimes makes a difference.

Its not unusual for there to be some pins missing on the monitor cable so thats not a issue.