Lots of people run i5-7400 or i7-7700 in this model based on user benchmark. there is a quantum leap in performance from 4core 6/7th gen to 6core 8th gen coffee lake, and unfortunately CL requires 300 series chipset not backward c/w 100/200. Intel forced user to buy new chipset for upgrade.
Inspiron 3268  has I3-7100 cpu running at 3.9ghz.  2 cores 4 threads.  Not bad but not as good for gaming.  Has anyone upgraded to an i5 or I7 with 4 cores successfully?   None seem to have the same speed on Intel ARK  Kaby Lake list.   Thanks for any info! 
Inspiron 3268 cpu upgrade