My family recently bought a D-Link Wireless AC1750 Gigabit Cloud ADSL2+ Modem/ Router Combo for around 200 bucks. This was to replace our 10 year old setup of a separate modem/router. I installed everything correctly on the wizard, so I decide to test it out. I jump on a TF2 server, and the ping was lower than normal, which was great. The ping then spikes for a split second, making the game glitch a bit, then everything goes back to normal. This happens every 10-20 seconds, and occasionally, it will maintain a 400-900 ping for a few minutes. This happens on all of my internet based games. I am puzzled, considering it is a top of the line router/modem, and it effectively doesn't work very well at all. Some help would be great thanks.
EDIT: My router/modem now often maintains a ping of around 2000 for about 10 minutes before dropping.
What probably is happening is that the router is lumping all traffic into a single queue, so that short packets (such as pings) get stuck behind the large file transfer packets. They won't be sent until those large packets (often, several seconds' worth) have been transmitted. The name for this condition is "bufferbloat", and its symptoms are that voice and video chat, gaming, and other applications work poorly when other traffic's on the wire.
Although a lot of people spend a lot of time tweaking their Quality of Service (QoS) settings, this is destined to fail every time a new protocol or application arrives - until someone tweaks the QoS settings again to make it work again.
The CeroWrt project has largely solved the bufferbloat problem without all that categorization and prioritization. I can up- and download files simultaneously while hardly affecting ping packet times, even though they're not prioritized at all. Check it out at http://bufferbloat.net/projects/cerowrt
Note: CeroWrt firmware only works in the Netgear WNDR3800 router. We push our changes into the OpenWRT mainline Barrier Breaker builds. If you don't have a WNDR3800 or use OpenWRT, ask your router vendor (or firmware distribution) to upgrade to support fq_codel and the other massive networking improvements available in the Linux 3.10 kernel. All the work at CeroWrt is open source and freely available, and we're desperate to have people help us "fix the internet".