Hello and Welcome to TSF,
Go here for ethernet driver:
http://www.broadcom.com/support/ethernet_nic/4401.php
Driver Sweeper:
http://www.guru3d.com/index.php?page=driversweeper
1. Use drive sweeper to remove any previous installations of ethernet drivers
you installed.
2. reboot pc
3. install the ethernet driver
4. reboot pc