Its this one:
http://www.asrock.com/mb/Intel/H81M/index.de.aspI have not installed anything so far. I have red about that alx stuff too. On the official Smos website. I have no Idea how to install those drivers though.
Are there other plug and play mining ditros that I may check?
http://www.asrock.com/MB/Intel/H81M/index.asp?cat=Download - at the bottom of this page are links for drivers and utilities (you don't need to install any utility - but you do need the drivers), just select your OS and download it.
As for your question, try BAMT, it's a linux based OS that's basically plug and play and designed specifically for mining, it also boots from a USB stick, so you can easily try it out even if you have windows installed already.
Here's a link to BAMT:
http://guiminer.net/bamtThis is a link to SMOS, which is similar to BAMT but has some bugs fixed:
http://www.smos-linux.org/installation/