You should look for a Vista driver, if possible, although Vista in general should detect most ethernet cards with a basic driver. Check device manager to see if it reports needing a driver for the device. If it already has one, go to network and sharing in the control panel, then manage connections and right-click for properties on the LAN connection. Uncheck IPv6 for compatibility reasons. If it requires a driver and you can't locate a Vista one, you can try manually/forcing a XP driver (via device manager), or if the driver has an installer run it in Windows XP SP2 compatibility mode (under properties, compatibility tab).