I havent even played single player I bought the game solely for multi I will try single to see how that goes. my psu is a kingwin kx1000 i do believe
So you're basically not hurting for power.
What are your framerates when you see choke points while playing?
Also, what is your screen resolution? Reason I ask is if you are running lower resolution (<1080p), your CPU will tend to keep more of the graphics load to itself.