This is a brand new 64-bit PC, built around a Gigabyte Z777-D3H Motherboard and an i7 processor. It has 2x1Tb SATA drives, one loaded with Windows 8 and the other with Ubuntu 12.04.
The wired network connection into my Belkin F1P1241ENau modem works with no problem at all, and a test install of Ubuntu 12.04 into a Virtual Box client also connects with no problem, but the installation on the dedicated 1Tb HDD will not connect. The messages I get are "Network Disconnected - you are now offline" and "No Network devices available"
I also tried connecting via a wireless USB dongle (which I know works fine) with no better results.
My old Dell 32-bit computer runs Ubuntu 10.04 and has no trouble connecting with the same cable and DSL modem.
Any help at all will be greatly appreciated.