Airport Card Extreme Very Slow Mac Pro

[SmartViewYTC]

Hey guys.
I just installed a original Airport Extreme Card in to my Mac Pro 1.1 runnig OS X 10.10.
The installation it self wasn´t too hard but the download speed is so slow.
With the WiFi Stick I used before, I was able to get around 50MB/s in speedcheck. Now only 3MB/s wich is very slow.
What is the problem?
I uninstalled the old wifi stick drivers already.
Maybe someone can help me-

Thanks

 

[MacVidCards]

Did you connect the antenas?

If you hold "option" when you click on WiFi icon it shows connection speed.

 

[SmartViewYTC]

Did you connect the antenas?

If you hold "option" when you click on WiFi icon it shows connection speed.

The antennas are connected. It shows:
IP Adress: 192.something
Router: 192. something
Internet: Unreachable (its german so I translate)
Security: Personal WPA2
BSSID: 44 something
Channel: 6
RSSI: -83dBm
Tx Rate: 7mbits
PHY-Mode: 802.11n


There was an issue that I couldn´t set up an Internet connection when I started the mac with the airport card for the first time, but after a restart it connected.