Hi,
Since the APM Command Center is not GA yet, this is one of the things that has not yet been completed. However our preliminary testing show that the server requirements are fairly minimal. I don't want to give you any inaccurate information, how many Agents are you considering?
Regs,
Florian.
PS: Since ACC is in "Limited Availability", you will not be able to download it from the CA Support site, you will need to participate in the CA APM Beta Private community and contact me to get the download link.