Low FPS in forts

[FrontierProject]

I've been running Skyrim for a while now on low FPS, I have a low end PC, 3.2 Core 2 Duo with a shared memory NVidia GPU (benchmark score 103). However after tuning the settings the past few days I'v gotten it to the point where I was pretty impressed, I now have nice FPS on with nice draw distance in the open world. My problem is that the game falls apart inside forts - or any similar stone building, prime examples being the ratway/ragged flagon - I don't know why it's forts in general, as the game seems to do fine in caves, houses etc, however the wooden Jarl's longhouses also see a noticeable dip. But nowhere near as bad as forts, I've noticed that if a fort is has multiple floors anything above the ground floor will be really bad, often to the point of unplayable. (ever tried aiming spells at 5-10 FPS, ain't gonna happen)

 

So basically I'm wondering if there's anything I could turn down that would help me with this without forcing me to play with lower settings in the rest of the game.

[blitzen]

Did you install anything that might have upgraded just the textures of forts/dungeons? It's possible that behaviour could occur if you had hires textures installed for those surfaces, but normal textures for the rest of the world. You can always check your texture folder and see what's in there. Check your .ini files too. You can configure interiors and exteriors differently, such as the number of cells to load, draw distances, shadows, etc. Possibly something in there is set differently for interiors, although you would expect to see that problem in other interiors too. Edited September 20, 2012 by blitzen

[FrontierProject]

I haven't added any texture mods, due to my low end PC, its definitely nice to know that interiors and exteriors can have different settings tho, I'll check that out. Edited September 20, 2012 by FrontierProject