Upgraded to PureFibre 1.5 Gbps download but speed remains 1 Gbps (and I think I know what I'm doing)

[news]

[wireless]

Telus fiber connection is 1500 Mbps down and 1000 Mbps up.
Telus modem is a Technicolor FXA5000 and its port 5 is advertised to be capable of 2500 Mbps.
I have Plugable USBC-E2500 2.5 Gbps adapter. So PC is not limited to 1 Gbps.
I have tried on two Dell laptops both the default driver and latest 2022 driver from the Realtek site:
1. XPS 4 core / 8 thread with Windows 10.
2. XPS 8 core / 16 thread with Windows 11.
Both Windows say its a 2.5 Gbps link. And logging on to the modem, it also says the port is using 2.5 Gbps.
I've also tested with 3 different CAT6 cables. Same result.
Whether it's speedtest web or, the speedtest app, I only get max download 1050 Mbps on laptop 1 and max 994 Mbps on laptop 2.
Telus technician who installed is actually unable to test the speed because his Telus laptop is too old. He called Telus and they insist the account is provisioned correctly.
How to fix this?


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