Network Adapter problem

I am using Gigabyte G31 s2l Mother board (*www.gigabyte.com.tw/Products/Motherboard/Products_Spec.aspx?ProductID=2693) , Intel dual core 5220 processor And 2GB RAM.
My problem is that there is no network connection. Nothing happens when I plug in the RJ45 pin (only light at the port glows)...
I installed the drivers given in drivers CD but of no use .
what to do ?

plz help me...