Suddenlink modem competitive gaming
 

I suck at gaming, my friend is getting lag. What is a good modem WI if that cuts down lag.

It's doubtful that your modem hardware is the cause for the poor gaming.

It's possible you may be experiencing a limited NAT type which could impact your gaming experience.

If you're connecting to your internet through a wifi connection you should change it to a wired connection if possible

If you haven't already, I'd put your console in a DMZ. This will open up all ports to your console and remove the majority of impediments you could be experiencing with your connection.

Dropping a couple hundred bucks on a high performing modem is unlikely to drastically improve your gaming.

There's a bit more to troubleshooting latency than just buying a new modem. Problem could be inside his house if he is on wifi, or congestion on the shared network for his area/neighborhood. What troubleshooting has he done so far?

That's a good point.

If there are multiple devices connected and you don't have a decent internet package you will struggle.

Does he have a wifi router sitting behind the modem?

There's a TON of stuff that needs to be checked to help with latency on cable.

Actually, I'd think that the modem would be the very last thing that you'd check. There are so many other larger opportunities for failure.

It's almost always the router. Whether it's NAT settings or the need for QoS.