> AFAIK there are very few (no?) 100Mbit ISA NIC's and so the conversation is moot.
There is, and I've written a driver for a zorro II prototype. Unfortunately, the TCP/IP software usually is already at its limits performancewise, and except for having a 100MBit endpoint, the speed gain is indeed moot.
Things might be different with Zorro III DMA, but this is a bit tricky. In any case you need to be using a different TCP/IP stack than MiamiDx (hey, where's Roadstar 68k, wasn't it to be release 5 years ago?), which is already at its limits when doing NAT/Gateway/PPPoE functionality below 100KB/sec with a 68060@50MHz. I haven't been able to push Miami above 800KB/sec at any settings.