During tutorial, if I alt-tabbed out of the game and back in, my FPS dropped down to 20. I can have anything going on outside of the game prior to launching it and then play it no problem, but the instance I alt-tab and back in, FPS drops to 20 and it will periodically jump up for a moment to regular FPS but go right back down.  

Specs - GTX980, i7-4790k, 16gb memory, istalled on 7200 rpm drive, W10 w/ creators update, 3 monitor setup all attached to 980.  

This happens no matter my gsync settings.