If you're here, you already know you love virtualization so it's tempting to, as new services come on board, add them to the virtual environment. But, be careful when you consider adding Data Protection Manager as a virtual service. If you do, you lose the key ability to fully protect Hyper-V-based workloads using DPM's native Hyper-V hooks. The reason: In order to fully protect Hyper-V with DPM, the DPM server requires that the Hyper-V role be installed on it. You can't install the Hyper-V role inside a virtual guest due to lack of VT/AMD-V capability inside the VM. Hence, you're out of luck.
Let’s talk specifics: In short, although you can still protect Hyper-V with a virtual DPM server, on the recovery side, you lose the ability to perform item-level restoration of items from inside a virtual machine.
You can still protect individual virtual machine workloads by installing the DPM agent inside the virtual machine's guest OS at which point DPM sees that VM as just another system to be protected.
My advice: Just go physical if you're deploying DPM, especially if you need that native Hyper-V support.