Have a look at the changelog in the mod’s description to see just how many cells have had occlusion panes added to them. While Skyrim already has occlusion culling, eFPS adds significantly more. It works thanks to occlusion culling, which prevents geometry you can’t see from being rendered. (I’ve been using Ominous ENB to give things a gloomy, somber look, but it costs up to 20fps in some areas.) If that’s you, exterior FPS boost is here to help. If you take advantage of the way Skyrim Special Edition handles heavy mod loads to tweak the heck out of it-and especially if you use an ENB to overhaul the graphics-you’ve probably taken a hit to your framerate.