Cooling

[GOD]

Ambient temp can play a part in high temps, you didn't mention what the ambient temp is. I've always enjoyed open chassis, it's the way to go. Also, which brand 1080 Ti do you have ?

One thing that you can also double check is the thermal paste. I've had times where I applied to much or to little paste and there wasn't a good mate with the cooler which messed up my temps under load but idle was only a little high.

Looks like he's talking about GPU not CPU.

GPUs have thermal paste, too

Obviously...