Do you have something like freezes for 1-2sec?
As for me, mainly this happens when T13 farm and 60+ GR. I tried 64 bit, game looks smoother, but still freezing.
One interesting thing, main pc with i7 6800k have like 0.5-1.5sec freeze (2x clients), while my second pc with i7 4770k have 3-5sec freeze (another 2x clients). May this happen because my 2nd pc get internet from 1st (motherboard have 2x LAN)?
CPU's sit max at 30%.