Infestation FPS drop and lag problems

[Fritte]

Hi i got fps drop in infestation on my new computer, it have a gtx 660 ti, i5 3570k and samsung ssd 120gb, so it shouldnt lag.
I have the latest graficdrivers and decent internet
Anyone know what the problem is?

[JDM-Hang]

%temp%,lower screen resolution,adjust for best performance,go to your warz folder and add a new text document,type in r_limit_fps 0 and r_limit_fps 0,then save as local.ini