My Specs GPU/CPU

GPU: AMD HD 7950

CPU: i5 3330 @3.00Ghz

So I recently got back into Skyrim, I absolutely love the game and have played the crap out of it since it has been out but there is one problem. I am currently doing the quest where you attack markarth with the Imperial Legion but when I come to the first line of defense I get a huge FPS drop and I mean huge, I go down to 2-3 FPS. I can normally play the game maxed out (All the settings as high as they can go) with about 60 FPS solid with no drops. It only happens at this point. Does anyone know why it does this?

Are you using any mods? Texture mods, enb series?

Do a game cache verify.

What jasper1979 say, and in addition turn Antialiasing off, if you have enabled it, and for sure DISABLE morphological filtering on in catalyst control center.

http://www.7tutorials.com/files/img/win8_app_crash/wac4.png

http://i54.tinypic.com/rc0hlt.png

It depends what your Control panel looks like.

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