I have the Verizon Gateway router (G3100) installed on the second floor in the center of our two-story house. ONT is on the first floor in the garage quite a distance from the router and is connected by COAX and Ethernet cable into the WAN port. The cable distance between ONT and router might be over 100 feet but I doubt it is over 200 feet. I also have a FiOS One STB connected via coax on the first floor much closer to the ONT. Verizon speed tests indicate the router is getting internet at 900-950 mbps download and upload consistently. Wireless speeds are 300 mbps upload and 150 mbps download fairly consistently, and wireless coverage from the router are good.
However, for some reason, no matter what CAT 5 cable I use and no matter what LAN port of the router I connect to, I cannot get wired speeds above 100 mbps for any device. Wired speed almost seems like it is "capped" at 100 mbps for some reason. Equally strange (to me, anyway): a just-purchased 100 foot CAT 6 cable gets no better than 10 mbps. Given that we have multiple adults and children streaming video all day long, we are trying to improve our wired connections so they at least approach the Gig service we're paying for. Any suggestions are appreciated as the Verizon troubleshooter is not currently functioning.