Unusably slow wifi (<1Mbps) on new Swift SF314-42

Last year I got a new Swift SF314-42 which is meant to be an upgrade for an older laptop. However the wifi connection on the new device is abnormally slow. I also have an existing Swift SF314-41 which I use for something else, and the connection on that is OK.

I wonder if there might be some interference between the two Swift laptops. When I completely remove the SF314-41 from the network, I have been able to get normal connection speeds on the new one. However this behaviour is erratic and on the most recent attempt I didn't reproduce it.

To put some numbers on it, old laptop (2.4GHz connection) and new Swift have download speeds 15-45Mbps on speed test sites. The new SF314-42 has download speed <1Mbps, and sometimes just shows blank or "No server available, please try again later". It is painfully slow to use for anything in practice.

Comparing the two Swift laptops should be a help to find the problem, but I haven't got there yet. They are both using 5GHz network band, channel 48. (Is it normal / correct to be on the same channel?) The slow SF314-42 has network adaptor Intel(R) Wi-Fi 6 AX200 160MHz (driver version 21.50.1.1), while the working SF314-41 has a Qualcomm Atheros QCA61x4A (driver version 12.0.0.948).

Based on previous questions, I have tried:
- I am comparing the laptops literally side-by-side, and they seem to have the same network signal strength.
- Remove McAfee from laptop
- Bluetooth off
- Windows troubleshooter for network adapter shows as working OK, and update driver says it's up-to-date

- As administrator: (1) netsh int ip reset C:\resetlog.txt (2) netsh winsock reset (3) ipconfig /flushdns ... and restart

Due to the pandemic, I've only tested all this on my own home network. I realise it could be good to see if the same problem occurs on another network, though ultimately I'll need to get them working on my home network.

It feels like I've tried everything I can, so any help very much appreciated!!

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Commodore_1995#

Have you ever used WIFI ANALYZER to check which channel is most congested?

Jer80

egydiocoelho. It looks like my neighbours are using 5GHz channel 36, while I'm using 48. The thing to watch out for would be if I was using the same channel as many other nearby networks?

Commodore_1995#

When you connect the sf314-42 and sf314-41 to another wireless network, does the problem also occur? If it doesn't, then I suggest you reset the router.

Jer80

egydiocoelho said:

When you connect the sf314-42 and sf314-41 to another wireless network, does the problem also occur? If it doesn't, then I suggest you reset the router.

Thanks. Unfortunately that is hard to do. I don't have access to any other network at the moment, due to covid restrictions.

Jer80

Update: I still think there is some interference between the two laptops, but it's maybe both ways. I've been disconnecting and connecting each of them. For a while today the SF314-42 was running fast (50-70Mbps), and the SF314-41 was a manageable but not super fast 10Mbps. Then without me knowingly changing anything, it switched back to the previous state: SF314-42 unusably slow and the SF314-41 50-70Mbps.

I agree it's hard for me to tell if it's a network or router problem. My provider claims the router should easily be able to handle several devices at once, and of course that would be expected.

Any comments still very welcome as otherwise all I can do is keep trying random things!