For a while I used a router to connect my two computers to the modem, but when the modem went bad and got the new one that I have it has enough jacks in it that I don't need the router. I do speed test on a routine basis and once in a while I will go into the modem software and see if everything is ok. But normally I just unplug the modem for a few minute and then plug it back in. That takes about 5 minutes for it to reboot and clears anything that I have acting strange. I think I still have the router in its box somewhere in all of my junk. I wish they would put fiber optic in here so I could get a higher speed. I am at the top of what paired wires will carry.
Ron