I'd say the fill port in no way affects gpu temps. I hope this guy only turned on the pump on the window side when filling up his res. Otherwise how do you fill this loop up without damaging the pumps?
Oh and to all the people going who are in love with the fill port, it's not something new, the first murdermods had this too

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Steffen's was smart because you can see how the pump has a constant supply of water. Still, you'd have to be careful about filling it up . . . . man, having a res is so much easier lol.
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