How about some more cheatcodes. Try pci=biosirq (could help if you get a irq conflict). Also you could unselect the PNP-OS in BIOS.
The output of at least the Ethernet Controller part of lspci -v could be helpful here, someone will probably know which module is needed, which you have to check with lsmod.
If the card is found and the module loaded you could try issuing ifup eth0 and running netcardconfig afterwards.

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