Here is a link to my website that lists what we have found to work for NV2.
Please be aware that the hard drive specs and network card are the 2 most important requirements. The hard drive specs we have listed are critical – fast hard drive not big hard drive and RAID. As you will see the network card we recommend is a gigabit card which also means that the rest of your network must match ie: CAT6 wiring and gigabit switch. Also note that you do not need to run Windows Server software on the computer that will function as the NV2 server.
This also leads into your requirement for online customers. Highspeed internet does not come close to the speed of a gigabit network. The best way I can describe NV2 is that it is a distributed computing model, this means that the workstations and server need to be equally powerful along with a high quality network.
If your online customers are mostly viewing and/or reporting high speed internet will be adequate. But if your online customers are trying to process payroll or some other database intensive process they will be unhappy with the speed. Please remember that your online customers must have a NV2 license on their workstation to be able to access and use a set of books from your server. To compensate for the speed issue you may be able to serve online customers by implementing a terminal/citrix server model but you would need to test it thoroughly before committing to it.
We have found our customers to be happy with the performance of NV2 when they carefully follow these specs. I trust that you will find this information helpful.