Get a Mediator and a 100mbit PCI Ethernetcard instead of that PCMCIA adapter.
The pricey Mediator 1200 SX is only necessary if you are keen on using ATX PSUs and really know how to fill 6 PCI slots.
Otherwise get the Mediator 1200 LT4 with four PCI slots. You can put in a Voodoo3, Ethernetcard, Soundcard and TV-tuner.