New motherboard for HP new problems

Well now the wireless has a hard time finding the networks anyplace. Sometimes it finds all and other times it finds none. Then 20 mins later bingo it found the network right here next to the laptop. The router is 20 feet away. Never had a problem with the wifi until now when I got the machine back. Did some more research and find the AMD chip running Vista on HP machines has been a problem. I have a question, buying a wireless card and turning off my wifi button on my DV2214 laptop, would that fix the problem?? Seems sending the machine back again is well ... And if a 40 dollar wireless card is a fix why not???