Configuration Standards Required for PCI DSS?

Hi all. I have a question around if Hardening/ Configuration Standards are required for the following devices or systems. The PCI standard v2.0 is not prescriptive enough to know which ones are required or not.

Your help would be much appreciated, in terms of guiding me if I do need standards for them as per PCI requirements.




Point Of Sale Devices

EMV/ Card Printing System

PGP Encryption

Database encryption

Configuration standards are mainly for operating systems and infrastructure software. But as always, it depends of your QSA.