I had a functioning Skyrim SE Step 2.3 build that worked extremely well, very good performance, etc. I switched to a Vortex setup at one point to play a collection and then decided I want to switch back. I did a full uninstall of Skyrim (full cleanout, I got the AppData and My Documents/My Games, etc. folders) and now I'm trying the STEP build again from scratch and this time I'm having a huge problem - the performance is absolutely awful. Load screens take huge amounts of time, game freezes every time it loads a cell or goes through a world transition.
I got through to the smoke test part with no issues but these insane performance issues began after I installed the rest of the mods and got to the performance testing state.
I'm run extensive tests of disabling mods and I can't nail it down to any specific mod. It seems the problem is simply caused by having mods, regardless of what they are, as crazy as that sounds. I got to the point where all I had left in the load was the bare minimum for the smoke test + USSEP + Alternate start (for easier testing). And this works fine. The second I start adding mods back the problem is reintroduced regardless of which mods I'm adding and it gets worse as more mods are added back.
It also seems to be some sort of caching issue. I'll disable a bunch of mods, start playing on a new save in a particular city or particular area of the map, first it's a bit slow, then it works fine, so I think it's fixed. I'll add one more mod back, start playing in that same area, same thing - bit slow at first and then it's fine. But then I'll go to another area of the map and the performance is massively worse. It seems to be that every time I increase the number of mods in my LO (regardless of what the mods are), each area of the map will be godawful slow to play through for the first 15 minutes or so then be fine. This makes no sense at all. Do I have to enable 10 mods, travel the whole map, enable 10 mods, travel the whole map, etc. until the whole install is done to be able to play? How does that make sense?
I know this can't be an issue with my PC hardware or anything like that because I had a previous build that worked perfectly fine.