Just wondering whether the ethernet interface, on pc's, is MDI or MDIX

Try IEEE 802.2. That's the most common.

The other terms your are using are file types.

Don:

MDI, MDIX and Auto-MDIX are interface types. Basically the equlivelent of DCE and DTE devices back in the modem days.

Auto-MDIX is getting quite common. Avoids things like needing a crossover cable to talk directly to a DSL modem or having a port called 5 and uplink that you can't use together on switches.

Medium dependent interface - Wikipedia, the free encyclopedia

I know that, what the heck was I thinking!

Thanks for catching my case of "The stupids"