I have a netgear FA310TX network card that has given me some trouble with the card trying to autonegotiate it's speed in knoppix as well as other OSs, and the solution has pretty much been to lock the card down to 10baseT and turn off the autonegotiation feature which would get confused and cause the link light to just flash on and off and move no traffic.

To lock this card into 10baseT in Knoppix:
1. Boot up Knoppix
2. switch to a virtual terminal (ctrl+alt+F3 will do the trick)
3. remove the tulip module " modprobe -r tuilp"
4 reinsert the tulip module but add this option "insmod tulip option=9"
5. switch back to the desktop (ctrl+alt+F5)
6. run the network card configuration ("K" > Knoppix > Network/Internet >Network card config") and setup your ip address settings here now that the card is working.

This should lock the card into 10baseT mode and should solve any speed autonegotiation issues you may have with this card.

Enjoy!