Baron623

Make sure the mounting is correct and has even pressure across the whole chip, also if your rad and intake fan for the AIO are on the bottom move them somewhere with better airflow on the side or top of the case so it's not obstructed by the floor or in a tight spot to be pulling air in or out, Jayztwocents made a video where he goes over the thermals of the shift and sets it up to get the best temps possible, don't remember which one it is but it's a more recent video from a couple months ago.

If you mount the Radiator in the top you will be fine.  However if you mount it in the front like I did then you won't be able to mount any drives. 
 

Have you tried booting with only the second cpu? 

Yes, you will be able to run them over 60 fps.  They are only available on the Windows 10 store.  Quantum Break is only available there so I would assume the same

first an overclock is the most likely source of the issue. if it happens again run your cpu on stock.
but if restarting the monitor solved the issue i bet its windows beeing the unstable mess that it is.

#RAMGate
 
get GPU-Z and monitor your GPU Clocks
also bring up task manager to monitor your CPU utilization
since you now have two monitors you can have it all at the same time
 
grab a screenshot when you get the FPS dips and post back with pictures