Major problems with new modem and router

[Mince]

Hi. My ISP is CenturyLink. I've recently replaced my CenturyLink-branded modem (which functioned as an all-in-one, with extra LAN ports and wifi) with this TP-LINK modem and this TP-LINK router. I have everything hooked up as expected--the RJ-11 connector is hooked up to the modem. An ethernet cable connects the modem to the router. Three computers in my house are connected to the router. In general, the internet works--it worked immediately when hooking these new devices up, without any setup.

 

However, I have been experiencing issues at a growing rate. Internet service randomly cuts off. Certain sites either don't load or take an extraordinarily long time to load. For example, YouTube, Facebook, and Google work fine. I've played games like L4D2 without any ping problems. Wikipedia takes a long time to load. Certain images on Twitter won't load (Vines won't load at all). This site takes a very long time to load, it takes like 30 seconds just to load a certain forum or thread.

 

From what I can tell from my research, this might be a result of the modem and the router conflicting in some way. However, I can't figure out a way to actually configure the modem. I can get to the router's page by typing "192.168.0.1" in my web browser. It allows me to configure a lot of things like wireless, DHCP, some security settings, and the DNS. I tried changing the DNS to OpenDNS and Google's DNS, but neither seemed to work very well at all--next to no sites would load with those DNS settings. The bottom of the modem says I can connect to it at 192.168.1.1, but this doesn't work. None of these issues were happening with my old CenturyLink modem/router combo. Unfortunately, it has already been returned to CenturyLink and I no longer have access to it.

 

Any ideas as to what I can do? It seems to me like the modem isn't configured properly. When I try connecting directly to the modem from my PC, nothing works at all. 192.168.1.1 doesn't work. It says there's an unidentified network with no internet access. I can only get a connection when going through the router. The Amazon reviews for the modem gave directions for configuring it for CenturyLink, but they involve going to 192.168.1.1, which doesn't work. Any help is appreciated.

 

(Sorry for typos and such, even editing this post takes like 20 seconds. Forgot to mention that these same problems occur on other computers in the house and on my phone.)

Edited January 26, 2015 by Mince