Yes, you can run with on 512MB of RAM. As long as you don't care about performance and will have only, at most, a handful of users. I ran JBoss AS on a laptop with only 512MB once. It was not that much fun. ;-) The wiki formula is probably a better bet. Typically, I prefer 2GB of RAM to run a single instance of JBoss AS, usually using about a 1.2GB heap. That should run a large number of user (hundreds or thousands, depending on the level of activity). If you have fewer users you can get away with less RAM. I am running JBoss Portal for our department on a system with 1GB RAM. That system also hosts the MySQL database used by Portal. But then our users number in the tens, and activity is very low. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4200160#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...