If you are using this as purely a "music server" only, then I think the differences will not be that great. That means the computer can act as the sever (or file server), but you will need a DLNA Renderer/Player devices that accepts the streamed music data and clocks the data to generate the S/PDIF or USB pulses for DAC.
In your case, I think you'll be using it as both a Server and a Player, since you are connecting a DAC directly to this. If you use a computer, many people have had good results with the JCAT USB card or other custom audio USB cards (think Paul Pang). You will likely want to get the best power supply (linear power supply if possible).
With a stand alone music server, some of them have fully linear power supplies and good clocks for generating the timing on the pulses (for different bitrates and sampling rates). The linear power supply makes a significant difference in the digital transport.
In your case, I think you'll be using it as both a Server and a Player, since you are connecting a DAC directly to this. If you use a computer, many people have had good results with the JCAT USB card or other custom audio USB cards (think Paul Pang). You will likely want to get the best power supply (linear power supply if possible).
With a stand alone music server, some of them have fully linear power supplies and good clocks for generating the timing on the pulses (for different bitrates and sampling rates). The linear power supply makes a significant difference in the digital transport.