Thanks for your help, Kevin. However, I have found a solution. I was posting originally in the support site of my ISP. It was the guys there that suggested I get the adapter. They also advised I get...

My home broadband is supplied by Virgin Media 350Mbps fibre. I have a Dell Inspiron 15 5570 laptop. It comes witha Dell GigabitEthernet adapter but I am told this is limited to 100Mbps by the Realtek...