Did everything and it is still -blam!-ed. Start the game, 141 fps, play crucible match, still 141 fps, go to tower and back to crucible, suddenly, 70 fps. Started a new game now, fullscreen, 59-60 fps. Switched to windowed mode at 1280x720 resolution, 59-60 fps, switched back to 1440p, still 59-60 fps. Enabled Xbox Overlay, 120 fps. Set rendering resolution to 25% - 60 fps, set it back to 100% - 60 fps. Played a strike with performance graph overlay active. CPU and GPU were around 50% the entire strike and I was at around 60 fps. I wonder what you messed up with the last patch before this Season, but you really need to revert it.