TP-LINK TL-WN722N Wireless Adapter High Gain IEEE 802.11b/g/n USB 2.0 Up to 150Mbps Wireless Data Rates Support 64/128 bit WEP, WPA-PSK/WPA2-PSK, Wireless MAC Filtering. Would this work for you? it is usb and you would not have to open the case of your computer.
Thank you for your help!
I have now ordered a PCI card:
TP-Link TL-WN951N Advanced Wireless N PCI Adapter
But if I have any problems with it I will try one of your suggestions.
Many thanks for taking the time to reply.