Nighthawk ac1900 wifi cable and modem lag issue while gaming

[Figguh]

I bought my Nighthawk AC1900 modem/router yesterday and managed to set it up using WoW internet easily to avoid using their modem that had seemed to break on me but now when I am gaming on Final Fantasy 14 I get some lag that I never got before. I used a Nighthawk X4S router before and never got any lag like this with the modem that WoW provided. I'm not completely sure if it is my game itself or the new modem/router but wanted to ask for help here and to see if anyone else has had any similar issues. Thank you.

[FURRYe38]

Is this the C7000 model modem? 

[Figguh]

Yes it is

[Figguh]

I'm debating on just getting a modem and going back to using my Nighthawk X4S again because I'm pretty sure that was working

[FURRYe38]

Are you gaming while wired or wireless connected? Wired is preferred. 

What ISP speeds UP and DOWN do you pay for? 

Any other bandwidth in use while gaming? 

[Figguh]

I am wired while gaming. Best way to do it after all.

My plan is 500 mbps for download and 50 mbps for upload.

There are a around 4-5 other devices connected and in use while I am gaming

[FURRYe38]

Sounds like QoS isn't handling what going on well. 

[Figguh]

QoS? And I'm going to get a modem and go back to using my Nighthawk X4S with it to hopefully fix the issue seeing as I had no issue with it and it was the old modem that WoW gave me that was the issue from what we figured

[FURRYe38]

As a test what happens i you bridge the C7000 and connect your R7800 router to it?