Question GPU temps go so high if I open Nvidia shadowplay or run game at a lower resolution (NONE FULL SCREEN)

[SomeGuyonTHW]

here is related to cooling and temps hope I'm not wrong.
so yes, my GPU temp is less than 50*c (rtx 2070)
while playing games like Minecraft with RTX.
but when I press ALT+Z to open Nvidia shadow play or WINKEY+SHIFT+S to take screenshot with snipping tool, temps go +60 or even 70, sometimes reaching edge of 80*c!
almost 30 degrees difference for opening an app overlay in-game? why?

this also happens while I don't run game at full screen (This one only happens with Minecraft with RTX)
Whats wrong with my GPU, is it game itself that has bad optimizations? I did all I could for cooling, I take lots of screenshots during gameplay (because thats what I do)
and it really annoys me...
(the second one I wrote about res isn't a severe pain, but it exists for some (OR NO) reason.)
thanks.

 

[drivinfast247]

Is your game being locked to a certain framerate? When you bring up the overlay or alt-tab out does your framerate go unlimited?

 

[SomeGuyonTHW]

Is your game being locked to a certain framerate? When you bring up the overlay or alt-tab out does your framerate go unlimited?

Yes I capped my fps at 60 with V-sync ON & No, even after bringing overlay fps is still capped at 60.
and what about res? is that related to game or anything?