Lost internet connection in 12.3

This morning when I sat down at my machine, it was locked up with a black screen and unresponsive to the mouse or keyboard. Something went bump in the night. I rebooted it a couple of times, got the desktop back and everything seemed to be working except that I had no internet connection. Other machines that are connected to the router have access. I changed the port connection, no go. I changed the cable, still no go. I reloaded the driver, still no go.

My configuration is:
Gigabyte GA-P67A-D3-B3 motherboard with on board LAN
Yast tells me that the network card is GA-EP45-DSS motherboard
Driver is Realtek r8168 (8.036) for PCI Express Gigabit Ethernet Controller
Processor is Intel i5-2500k
Router is Linksys WRT54GL

I am running 12.3 with Linux 3.7.10.1.1 desktop which has been flakey since I put on some updates a month or so ago. I decided not to try debugging it and would wait for 13.1.

I don't know what to do next.