Help make my game playable

[erratik]

Hello all

I'm having big problems with this game and hoping you can help me.

Like others, the problem I have is bad FPS drops and stutters constantly.

I've read a few threads here and many people have older systems than I do and can play the game relatively smooth with good FPS. Some even on high settings so i'm a bit confused.

Here's some things i've tried so far with very little difference and the game is still unplayable:

-every game setting (verylow, low, medium, etc...)
-clouds off
-forests off
-buildings low
-ground low
-shadows off
-flying over water (apparently better performance for some. no different to me)
-all settings in nvidia control panel to fastest performance for launcher.exe
-different AA settings off, forced and in game
-forced vsync, triple buff, etc
-disable antivirus
-Nvidia Driver 270.51

Is there anything else I can try? All I want is to be able to play the game smooth. I don't even care if graphics look crap anymore. Please help before I have a breakdown

This is my system:
WIN 7 x64
Asus P8P67 PRO
Intel i5-2500K @ 4.4 GHz
Corsair XMS3 4GB DDR3 1600MHz
MSI GTX 460 HAWK 1GB (overclocked little)
20" monitor 1680x1050