@David941 if your son'sXbox is not getting over 100Mb/s over a direct ethernet connection it sounds most likely to be a dodgy cable or less likely a misconfiguration of the xbox. You need a cable with all 4 pairs of connectors working to get Gigabit speeds if one core is broken you get a max of 100Mb/s. Download speeds will vary for a number of faxtors including server load but you should see will over 100Mb/s. Of course if the cable connects via powerline adapters or connects to a wifi extender those can restrict spedds.
Measuring speeds accurately requires use of a single device connected to the hub by a working Gigabit Etgernet cables. Tests over WiFi with other equipment connected are unreliable as you usually end up measurung the speed of the WiFi connection between the devicexand the hub. WiFi spedds depend on the layout and type of construction of your home.
With a 900Mb/s connection you should reliably see speeds up to 900Mb/s at quieter times and only go down to 600Mb/s at peak times - you share a connection with up to 29 of your neighbours which has the capacity of 2.48Gb/s.However in practice few people including your family will use more than 100Mb/s.
Sky test the speed to your hub every day, you can see the latest result in the Service Checker in the My Sky app if you click through you will see the history for the last few weeks if it falls below 600Mb/s for 3 days the app,should offercsupport.
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65inch Sky Glass, 3 Sky Streaming Pucks, Sky Ultrafast + and Sky SR213(white Wifi Max hub) main Wifi from 3 TP-Link Deco M4 units in access point mode
