Fastest speed connected to a lan port is 840mb.

 When I connect my pc straight to my modem I get 1400mbps. 

I understand the lan ports are only gigabit ports but why can't i get close to a gig? I've reset everything. Turned off prioritize (standard). I've done everything I've researched on how to speed up the router and its starting to irritated me now. Any suggestions is appreciated! 

Thanks