You should be fine as you'll still be able to share up to 54mbps across all your devices via 2.4ghz only. It's worth being aware though that if you have a lot of stuff going on and are pushing near the 54mbps limit, you may reach a wireless bottleneck and see some latency issues.
Glad to hear you have a better experience on 2.4ghz. It sounds to me like Plusnet router doesn't handle the new wireless card on your laptop well
Although you've solved it, it's not ideal.
You have 5 options.
1. Keep the laptop on 2.4ghz and risk not being able to connect to modern networks...
Turn off "allow the computer to turn off this device to save power in the Wireless Adapter Properties.
In the adatper settings advanced You'll have a property of 802.11n/ac wireless mode or similar. Disable n and ac and it'll force you to 2.4ghz (you'll want only 802.11b/g)
Its also worth reviewing any security software installed as something else could be impacting the connection.
Before you take a punt on a new router, check the laptop works consistently well on wifi elsewhere.
Also, you might want to force the wireless adapter to 2.4Ghz and see if that...
Thanks. It looks like you are connected without issue on 5G (802.11ac) and the connection is stable so, there's no connection drop which is good news.
Given it's stable, it does point at a driver/software issue, although I can't rule out some weird Wireless setting compatibility issue on the...
If you can run the diagnostics and send them over, I'll happily review them and I'll then know exactly what is going on. It does have the feel like of wireless hardware/driver or 3rd party software if you have full line of sight
Ok, does the problem happen when you're next to the wifi router - i.e. within clear line of sight?
It could be related to interference (fireplace, microwave, etc.)
If it's still crappy, I'd look at the wi-fi adapter drivers as you rightly say and any management software on the device. If...