Frame rate is very Broken

[Truman_2]

I have built my new pc and I wanted to try out some games (what the pc is going to be used for). I launched the game Rainbow Six Siege, in the game I was getting around 200 FPS. I finish playing the game and install a game called rust it runs well also. I go back into rainbow six and I am getting 40-50 FPS. I have tried restarting my pc and uninstalling rust. What should I do to get my frames back?

 

[Kkody2]

I have built my new pc and I wanted to try out some games (what the pc is going to be used for). I launched the game Rainbow Six Siege, in the game I was getting around 200 FPS. I finish playing the game and install a game called rust it runs well also. I go back into rainbow six and I am getting 40-50 FPS. I have tried restarting my pc and uninstalling rust. What should I do to get my frames back?

What are your specs for your PC?
Knowing these could help determine what frames you should logically be getting in these games.

 

[Truman_2]

I have an 8700k (with kraken x62 cooler) and a corsair hydro gtx 1080ti. On a 2560x1440 monitor