This is a really easy fix if your wifi download/upload speed on your Windows Laptop/Desktop isn't giving you the speed it should be.
Your Windows device is set to automatically select your wifi connection in the Network settings when it could give you your 5GHZ much faster setting. It is possible of course that your router is an old one and doesn't support the latest connection speeds in which case I recommend you call your ISP and ask them to send you a new router. If they want to charge you for this then tell them you have a much better offer and will be leaving them asap and have a look at the latest packages from Plusnet who we have used for many years.
So try this out, it increased my laptop wifi speed from 27MBs to 49.5MBs as you can see from this short video, so it has to be worth a try!
Let me know if this speeds your device up!