Seems VIA’s Athlon chipsets, specifically the KT600 in this board, don’t much care for some common PCI wireless chipsets. All of these are actual PCI devices, not on a Cardbus adapter card.
A Broadcom BCM4318 “AirForce” failed even basic PCI configuration; it was detected instead as a Gammagraphx device (0000:0040). Same card works perfectly in a system with nForce3 chipset.
A card with an Atheros chipset worked under light use, but caused random kernel panics under even light NFS traffic while acting as a file server. Under Windows, sporadic hangs were the result. Didn’t check if this one worked in the nForce3 board yet.
Finally after almost giving up, a card based on a Realtek RTL8185 worked correctly and reliably.