I've had my 2080 TI XC Black with a hybrid kit bought since Jan 2019, it's been running flawlessly this whole time and I literally never heard it run before, even when playing games.
 
I uninstalled the whole card 2 days ago so it's just been sitting on my desk for about 48 hours in an anti-static bag.
 
Today I installed it into another computer and the pump is insanely loud. At first, the screen kept going black and I thought I had power supply problems, but when I checked GPU temps it was idling at around 90C, with the pump making insane noises. 
 
It's been about an hour and it has quieted down a little bit but it's still quite loud and idling around 58C as I type this. There was no leaking nor was it damaged in any way that I can tell.
 
What could have happened to this pump in 2 days of sitting idle?
 
11G-P4-2282-KR is the card, XC Black, with the hybrid kit 400-HY-1384-B1.

How's your radiator vs pump placement? https://youtu.be/BbGomv195sk

Reports of pump issues and being over by a 100 from buy point kept me from pulling the trigger on the ftw3 hybrid yesterday on b stock. Esp since they have only a 1 year warranty.

I figured out the problem.
 
Apparently a tiny bit of air in the impeller can get stuck there and the solution is to flip the computer on it's side for a moment to let the air get pushed out. Solved it almost instantly but this was in an HTPC so it wasn't as easy to get to as it could have been. No amount of tapping the pump or jostling with the hoses/radiator helped, the pump itself had to be turned 90 degrees. 

Yeah, this thing I thought reading first post - air trapped in pump, thats why pump is load plus no water circulation results in instant overheat as pump is stopped.