Thank you !

Well, I think I'll buy 4 Athlon 2ghz (I got a good price for those), so It willl be "compatible" with Windows and easily with linux (There's no problems with Athlon and Linux?) , and it will give me some "room for manoeuvre" (can we say that in english? :| ). And I'm going to use wireless cards and a router (no cables everywhere in the place !). And it's not going to be connected on the net so I don't really worry about somebody hacking in my network (since it's wireless). Also, I already have 3 computers on a router so I'm going to plug it into the firewall for testing exploits etc. Do you think it will work?