Hi Joe,
thanks for the help.
1. Yes I know. However dell is not supporting any kind of such upgrade. I am by myself here.
2. I just booted Windows 7. The tests give exactly the same results (12Mbps download, 70Mbps upload). I strongly believe it is not a problem of drivers. It happens in Linux too.
From your answer I guess the problem I have should not exist.
Is it possible to have such results if the antennas are not connected to the right pins?