WinPcap load capacity

Hi. We are trying to run low tests on a VoIP recording application based on WinPCAP for audio capturing. We want to figure out what sort of server characteristics we need to use to hammer the application with X number of concurrent RTP streams. For instance what we to come out with is something like this:

Concurrent RTP Streams CPU Cores (3GHz) RAM (GB) Drive Size (GB) 1 1 2 1 1000 X1 Y1 Z1 10000 X2 Y2 Z2

And so on it goes....

I have not been able to find basic information on system requirements. Any help would be highly welcome.

Thank you