Open FPS drops while looking to a specific direction

[KAIRAgcn]

Hi. My problem is when I look at a specific direction, changing camera angle, I am having fps drops. It happens everywhere (including map) except interiors which are inside (like tavern but when its outside like streets of a town, it happens there too).

Spoiler: Interior at the beginning

Spoiler: Battle area

Spoiler: Map

Spoiler: Interior

For some reason it's strictly limited to 30 FPS at here.

I tried re-installing the game and OS, all setting variations, using WarbandPatcher but none of them have worked.

CPU: Intel Core 2 Duo E7300
GPU: NVIDIA GeForce 9800 GT
RAM: 4 GB (3,25 is usable)
OS: Windows 7 Home Premium 64-bit