Iv been having many network problems recently, and it finely boiled down to my onbord network card dyeing on me

replaced it with a new pci realteck rtl-8139/8139C/8139C+

This card works fine under windows and on my ubuntu live cd

however it wont connect on my ubuntu instillation, if im right i need to correct drivers to make the card work

im slightly stumped onto how to do this though, and would be realy greatfull if someone could point me in the right direction