Frame rates going crazy by the ritual Stone

[wildtangent]

So I have been playing this current character for a little while now. Character lvl is 17. I decide to go to Valthiem towers, and as I approach the ritual stone my frame rates start to tank, and then start jumping all over the place.

 

Anybody have an idea of what might be going on there?

 

Ok think I figured out what was causing it. A mod called increased enemy spawns. Don't know why it hasn't been doing this from the start, but now I have to find another way to make this game hard. because even legendary is child's play in this game.