HOW TO RUN NETWORK

connect the 2 switches to the router, and 40 computers to the 2 switches, that's pretty much your physical network done.

depends what your gonna do and software your gonna use you may have some restrictions with computers talking to each other with windows.

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You're pretty brave taking this on but as the previous poster says, it's as easy as that - physically. To advise further, posters will need to know which software the 40 boxes are using and whether you're going to use one of them as a server. Linux is better - in my opinion - at handling the server role but it all depends on what the 40 machiens are actually going to do.
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