Welcome to the club! So many of us have experienced failed wifi card - mine exactly one month after the warranty expired. Also, many of us are suffering from a message box that constantly pops up indicating that a network device has been disconnected - even when we have wifi turned off since the damn wifi cards don't work anyway.
Wish I could give you some positive news on this, but short of having the wifi card replaced, not sure what other advice I can give you.