Hello Jordan,
There is no rule of thumb for the server needed. Generally speaking, CatDV server is hardware and storage agnostic. Your specific workflow and the usage you will make of CatDV is what will influence your hardware choices.
In the end, your safest bet is to work with an experienced system integrator who can analyse your workflow, and help you choose the proper hardware and the software components you will need. The NX3100 is a storage server, so you also have to make sure you will get proper bandwidth and storage for the work you want to do with CatDV
I would be happy to chat with you about it. I'm based in Toronto, but I work with customers in Calgary as well.
Cheers,
Sebastien
sebastien at ordigraphe.com
1-888-444-2600
Sebastien Bertrand
Ordigraphe Inc.
Toronto, Canada
http://www.ordigraphe.com