How do i know whether my NIC works or not?

[Christian Schult]

Hello arshad,

What Ubuntu version are you running, what is your kernel version? Which
kernel modul is loaded with your NIC?

$ cat /etc/issue

$ uname -r

$ lsmod | grep r8

$ lspci -v -s 03:00


Support for your NIC is in linux since kernel 2.6.28, if i googled it
right. Maybe there's a problem with that modul or with hardware
detection?

Perhaps you can replace the NIC with another model just for testing
purposes?

Btw.: comment out the lines belonging to eth0 in /etc/network/interfaces
if you want to configure the NIC with network-manager again (that GUI
thing you used before).

Christian