configuration is the key to success. once you've walked through it, it really is quite easy. add 3c5x9cfg.exe to a dos boot disk, and program the card to have the correct info (auto config can be used as well).

vector was quite easy being based upon slackware the same procedure can be used. using an editor, went to /ect/rc.d/rc.modules, and removed the # sign in front of the network card module so it will load when the system is booted up.
if not performed already, netconfig can be performed in a terminal. vasm can be used to do the same.

not sure if my memory is accurate for dsl.8, which is based upon knoppix/ debian. i think (i checked, and corrected) i added the lines:
to /opt/bootlocal.sh. i get a question if i want to use dhcp each time i reboot. modprobe and netcardconfig will have to be manually performed if using as a demo distro. some say pump can be used in the place of netcardconfig.

(editing performed as root)

a half a dozen of these cards were useless untill i got the procedure figured out.

btw all of the ones i have are variations of the 3c509b isa NIC

http://support.3com.com/infodeli/inotes/techtran/727e_5ea.htm
http://www.urz.uni-heidelberg.de/Netzdienste/nm/misc/3comnic/
http://members.driverguide.com/driver/detail.php?driverid=65551
http://developer.skolelinux.no/~klaus/notater/x947.html