I would like to use JBoss for a java application which is
used by 350 persons an, where can I find more informations
about the hardware requirements.
OS dosn´t matter, it is all posible for me(Win / Linux).
you find this information anywhere. You would need to either suck it and see, or get one of the jboss guys to consult on your app. There are just way too many variables involved.