Terence EdenVirgin have also upgraded me to Gigabit fibre.
Which, as I wrote a few years ago, is mostly pointless.
https://shkspr.mobi/blog/2020/12/whats-the-point-in-gigabit-broadband/
I wonder when gigabit will actually be useful?
What's the point of Gigabit broadband?
(This is a curmudgeonly post which is going to look ridiculously outdated in a few years.) My yearly contract with my ISP has just come to an end, so it was time to shop around for a better deal. They presented me with the following monthly options: Drop to 100Mbps for the same price I'm paying today (£44) Keep at 350Mbps for a tenner more (£55) Rise to 500Mbps for a fiver more (£49) Go to GI…
Anyway, if you want stupid fast Internet, sign up using this link and Virgin will both give us £50.
Using iperf, I can get a max of about 940Mbps between machines on my LAN.
I suspect that might be a limit of my router, USB-C Ethernet Hubs, and ancient cabling.
Most Internet speed tests simply can't handle gigabit connections.
Cloudflare's gets to about 900Mbps which I suspect is about as is good as possible.
But the reality is almost no service on the Internet can support gigabit home connections.
Dr. David McBride (dwm)@Edent TCP? Might be an interesting experiment to try enabling the `bbr` TCP congestion control algorithm and trying the test again:
echo 'bbr' | sudo tee /proc/sys/net/ipv4/tcp_congestion_control
(I gather there is a similar incantation for Windows.)
@dwm Into the client, server, or both?
@Edent Sending side of any bulk TCP flow. (Both if unsure / doing a bidirectional performance test!)
@dwm hasn't made a noticeable difference. I suspect the older router is the likely culprit.
Gary 
@Edent @dwm the core problem with gigabit ISP speeds is that they’re usually connected using PPPoE, and most home router/firewalls run a variant of OpenWrt. OpenWrt is Linux based, and its PPPoE daemon is single threaded and CPU-bound. The CPU just isn’t up to forwarding enough packets per second to maintain gigabit throughout.
For Linux based routers you need a beefy Intel CPU. The option is a BSD based system like OPNsense.
This is 5 years old, but still relevant:
https://forum.openwrt.org/t/so-you-have-500mbps-1gbps-fiber-and-need-a-router-read-this-first/90305
So you have 500Mbps-1Gbps fiber and need a router READ THIS FIRST
It's such a frequently asked question over the last few years that we really need a post we can point people to. So your cable company rolled out 500Mbps or 1Gbps download speeds, or you have 1Gbps symmetric fiber (GPON/EPON) from ATT or Centurylink or Orange or whoever. You realize your old all in one router from 2009 is not up to the task of handling this, but hey by now stuff should be cheap and available that will handle your new fiber connection right? So you want advice about a router for...