After what seems like an eternity (3 days), I finally got my onboard LAN working. I figured someone out there must be going through the same trouble I was.

In order to get ethernet working, disable the PnP OS in BIOS. Yes I know this is already in other topics on the forum, but this will just shorten somebodys search someday.

If anyone else has any tips on getting Knoppix to run on the Asus P4S8X-X motherboard, please post them.