Giving a D620 n capabilities

I would like to replace the 3945ABG card in my D620 with a card that has n capabilities, so I bought an Intel WiFi link 1000.

After replacing the WLAN card, I see that Windows (7) detects it, but it claims the card doesn't start. I got the latest drivers from Intel (they are the same as for the 3945 card) but it doesn't help.

Suggestions are most welcome.