The other week, I was configuring a laptop I was given. The wireless wasn't brilliant and stuggled to even see a few routers in my area.
START > Control Panel > System > Devices (Load Device Manager basically).
Find your Wireless Driver, double click it.
You'll see ADVANCED. In here (for my driver anyway), I found at least 20 different options with my laptop, my PC though only has 1 option).
I changed Compatibility to Broader Range. I doubt you'll have the same, but you could try changing settings to see if it gets a better lock on your router. If it doesn't help, just simply change it back.