New airport card.

I just bought a new airport for my macbook pro. It only connects to a wireless network when it's two feet away from the router. So I decided to try a new wireless card. I have the macbook pro with the serial number a1150. It's a 2.0ghz, but running snow leopard. So I ordered 802.11n card, the original card is g, I think?

I bought this card.

MacBook 802.11n Airport Extreme Card - iFixit

But from a different site. Anyways, I installed the new card and turned my mac on and it said no wireless card was installed. So I put back in the old one and it works, but still has the same problem. Do I need to install Apple's airport extreme n enabler?

Or could the new card be faulty?

Thanks for the help in advance.

Where did you buy the card from if not the ifixit site? The card you linked to from ifixit is the correct one for your model MBP and should have worked or at least be detected. Since it was not detected, it may in fact be defective or it's not the correct card. Did you look at it closely to see if they sent you the right one? You can try to install the Apple Airport Extreme N enabler to see if that helps. If it doesn't, I would send the card back for a refund.