Problem with broadcom network adapter

[#1]

When I connect via WiFi to my PC the first 10 seconds or so work then speed drops straight to 5.5mbps and no web pages will load at all.
All devices in the home now connect fully to the WiFi yet the PC has this problem.
It states that there is a connection with internet access but as said above no webpages will load up after the initial 10 seconds.

When I connect an ethernet cable up, everything runs fine and fast so this is a wireless issue.

Could there be a problem with the network adapter in the PC? I'm unsure though as it finds and connects to the router with 4bar signal.

[#2]

@andrewgreenwood 

Try separating the 2.4 and 5 GHz bands on your router. See https://community.plus.net/t5/My-Router/2-4ghz-and-or-5ghz-best-practice/m-p/1351966#M840

Try each in turn and use the best.

[#3]

Moderators Note

This topic has been moved from Fibre to My Router

[#4]

Hi @Baldrick1, I have already tried this with no luck. Even reset the router and tried this step again with the same result.

[#5]

You could try updating the drivers on your PC. I use the free version of Driver Booster. You will be nagged to upgrade to the paid for version so I tend to remove it after use.

[#6]

@Baldrick1 drivers are fully upto date, may just have to try my luck with a network home plug.