I was trying to install an EK custom water block on my 2080 ti. After I got the back plate off I was taking out the small hex screws and a very small tiny black rectangle fell off (or I knocked it off) now the card will not boot
There are no "extra" parts on the card whatever you knocked off is almost certainly mission critical. Unfortunately I suspect you learned an expensive lesson today. Maybe a pic will clear up what you broke but I figure it's toast
Yea, you knocked off (or the quality control is bad and it wasn't seated properly) a capacitor in the central circuitry of the gpu. I suggest getting it replaced. That card will never boot period without that essential piece.