KayPeters123

Your temps would've been high for stock speeds but seem normal if the system is already oc'ed.

^^ That's what I was talking about, GPU Boost 2.0. I forget what Pascal does, IIRC most of the higher end cards will boost themselves to 1900-2000Mhz on their own, usually a good bit above what the spec sheet says, but GPU Boost is very temperature dependent. They boost the best at or under 50C, every step of the way from 60-70-80-etc it loses a bit of headroom due to clocking lower for thermal's sake. 

You card is gonna be fine up to 85C, it just won't boost as high. 

Click "Display adapter properties for Display 1" go to the second tab in the window that opens and set the refresh rate there.
 
< You'll get a list of supported resolutions. So click what you want.