In my main pc upstairs (several years old) I a have a n150 wifi adaptor in my desktop. My new netgear router is dual band 5Ghz and also 2.4Ghz. I have seen a TP Link dual wifi adaptor in Argos reduced to £14.99. If I push it into my pc should my pc work on 5Ghz on the basis of the adaptor alone or do I need to change the internal pci/network card?
Pookie, your Netgear dual-band router will be broadcasting two wireless networks - one 2.4Ghz and one 5Ghz. When you've installed the TP-Link adapter, make sure you choose your 5Ghz network from the available ones in the list. It's as simple as that.