yes, I have set every single setting in Just Cause video options On, should I change something?
EDIT. Just checked, bokeh effect doesn't change my fps.
Is it really my dual core @3.6GHz that is bottlenecking?
Maybe but having a Intel rig my self (spare rig check profile for specs) the 775 platform sucks bandwidth wise to the cpu. Really the FSB really sucks since it tops our around 4-5gbs vs that of AMD and 1156/1356 which can easily be around 20gbs+ (rough figure).