i purchased, what was labeled as a 4-port fast ethernet sbus card from ebay.
i installed it in my ultra1, and it seems to be working fine. how can i determine if the card is infact a fast ethernet card vs. the standard ethernet 4-port card?
Look at the man page for the driver it's using. Fast ethernet drivers will have features to change speed and turn autoneg on and off. The only fast 4-port card I know is qfe and "man qfe" describes what it can do. But there may be others.
hmmm... i'd still like to know if there is a specific command... but i got lazy and looked at the switch lights... it is a 10/100 4-port card 
You could use the ndd command to show you the settings for your interfaces. I don't remember the exact options you'd use, but if you do
ndd /dev/tcp \?
it will show you the list of parameters ndd can report. One of them should certainly be able to tell you the speed.
The tcp driver won't know the link speed. How could it? There could be many links. You have to ask the card's driver.
ndd /dev/qfe instance n -get \?
would show the possible parameters for a qfe card. But unless you're already familiar with the qfe driver, you would probably do a "man qfe" first. And in any event you're back to needing to know the driver's name.
That's right of course. Use ndd on the particular interface, not on tcp itself. Now that you wrote that, I remember the ndd commands I was using to set link speeds were all done with /dev/qfe just like you say. Sorry I messed it up the first time.
danke to you both...
this goes in curious infomation file.