@Nanosecond exactly! I bought it for the same reason, to use it with gigabit speed on cable, which it doesn't deliver, and I returned it for this exact issue. The wireless insight was just to explain...

@Nanosecond Initially I also thought it was a problem in the speed negotiation between the router and the modem, but I found that the problem is different. As I said earlier, after creating a 5GHz...

Hi, @Biras ! In the end , I returned my C6 router because I couldn't find a solution to the problem.

I called the TP-Link technical support, and they diagnosed that my router has a problem. I am sending it back.

New information! When connecting my computer to the 5GHz (AC) Wi-Fi network, I get my full internet bandwidth. So, it seems that the router is applying kind of a limitation/QoS on the ethernet...

I have a 240/20 Mbps internet connection. When I connect directly to the modem using the same cat5e cable, the ethernet connection is stablished at 1000 Mbps (1 Gbps) and the internet speed reaches...