Here is my magic commandline.txt that gave me extra 20 fps.
I hope it helps someone.
-width 1680
-height 1050
-refreshrate? 59
-novblank
-texturequality 1
-renderquality 0
-viewdistance 0
-detailquality 0
-shadowdensity 0
-nomemrestrict
-availablevidmem 4.5
-norestrictions
-percentvidmem 100
-noprecache
-safemode
-fullscreen
-framelimit 100
-Noswapdelay
-Managed
-Usedirectinput
-Waterquality 0
-Waterreflectionquality 0
-Reserve 0.3
-ReservedApp 0.5
-Forcer2vb
-DX10 / High
-Minspecaudio
-Shadowresolution 640
-Reflectionresolution 640
-No_3GB
If you wanna change graphics settings after applying this commandline you need to do it via commandline or it either won`t save or will overwrite the commandline and will make it useless.