The only way to find out is to try it. Since it's ISA PNP, you might want to add a line like "/sbin/modprobe isa-pnp" near the top of /etc/rc.d/rc.modules. This will run a module that probes for ISA Plug 'N Play cards and sets them up. Put it before the execution of the rc.netdevice script which is near the bottom of the file. Then, either reboot or run rc.modules manually and try netconfig and see if it can pick up the card. I've found that the isa-pnp module in the 2.4.X kernels is more reliable and less error-prone than the older ISAPNP tools that were required in 2.2 and older kernels. BTW:, I just checked in the Ethernet Howto, and it mentioned a Netgear card that works with the 3COM driver. However, it was only a brief mention. Good luck.
