I've got the a7n8x deluxe with dual lan ports, my onboard (nvidia) lan works great. Sorry I can't offer any other help but good luck.
As a total newb to linux, let me be the first to say that I find it extremely user friendly. Everything except for the fact that I cannot get it to recognize my onboard LAN.
I have heard of trying to dmesg or lspci-vvv, but I think both of those are for PCI and not onboard. Can someone get me up and running with a step by step?
I've got the a7n8x deluxe with dual lan ports, my onboard (nvidia) lan works great. Sorry I can't offer any other help but good luck.
The on board lan also uses the pci bus. So the output of 'lspci -v' can show you if the on board lan is recognized by knoppix.
Is the problem that you don't have an internet connection? Meaby you have to configure the on board network card (lan).

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