I have had a problem with no wired Internet connection in 12.04 and my Atheros 8151 Ethernet card and I followed the procedure to replace the non-working driver (At1lc) with it's replacement the Alx. The procedure seemed to work very well until I re-booted and the original (At1lc) driver still appeared in my lsw -c network. The procedure I followed is described in
How do I install drivers for the Atheros AR8161 Ethernet controller?
I repeated the procedure three times and each time the process and result were the same. How do I deactivate the At1lc and activate the Alx?