Natural View Tamriel
could an issue with your ENB.
"in that case yes you are hitting you VRAM Limit you need to reduce some of the larger textures in quality. This is also why i recommend the Medium Setting of DynDOLOD I would start by reducing DynDOLOD to medium. Last time i tested i was hitting 4.5GB (ish)."
Do you run your game at 1080p or 1440p?
I run the game at 1080P since the highest resolution our monitor can do.