Practically unusable internet but only on one device on one network

Okay, this is pretty confusing. I've had the laptop I've been using for about 6 months now. It's a Dell G7 with a Killer AX1650i card in it. I've just moved house and my internet is working fine on every device (older laptops, phone, TV, wired devices like my NAS and PC) except this. Doing speed tests, the download speeds seem fairly respectable (always above 50Mbps and usually in the hundreds) but uploads are stuck at 0.1Mbps. But even then, just web browsing is not smooth at all: pages load slowly and hang often.

It's my only device with WiFi 6 but I only have a wireless ac router - same as at my old place and other places I use my laptop. It's only on WiFi and only on this network. I cannot for the life of me work out where the issue could lie. It seems like it's a problem with the laptop as all my other devices are fine but why does it then work fine on every other network? It can't be a problem with the WiFi signal either as copying files to and from the NAS go in excess of 500Mbps both ways.

Any ideas of things to check?

 

I would take the laptop to the router and connect it by ethernet to be sure it connects properly to the internet - this would help to eliminate a local software problem (firewall,..). If you are using a VPN on the laptop, disable it and check configuration in detail. Next, check the 1650 card - reinstall drivers, check all settings. An additional step would be to open the laptop and check to be sure the card is seated, and that all connections are intact.
Keep us posted.

 

Follow this guide to remove and block the application software that comes with the Killer WiFi card and stick only with the drivers.

 

That's am excellent suggestion. The Killer 1650 is equivalent to the Intel AX200, and uses the same drivers. I have not found the Killer software to be helpful - even before Killer was acquired (at the advice of helpful folks here), I deleted all of the Killer software and have just used the drivers. This leads to much better, more consistent performance. I would guess that this may be your problem.

 

The AC router is not identified but it should be using the newest firmware.The security should be set to WPA2 AES ONLY.
Channel selection on both bands should be the least used by your neighbors.
The free inSSIDer program will let you see the channel usage and your signal strength.
Optimal wireless is usually about 6' from the router and in line of sight.Walls,Floors and distance will cut signal strength.
The sites you connect to and time of day will also have effect on speed.