If you want to use Provisioning Server auto-add then it’s a good idea to setup a default auto-add device collection.  Auto-add will create a target device in the farm and assign a blank vdisk to the target device.  The device will be added to the default collection and will be configured to boot from the device’s hard disk (which is helpful if a device boots from the network but isn’t a PVS target device).

Create a blank disk.

Change the disk to standard mode.

Create a new device collection.

Create a new target device and set the device to boot from hard disk.

Assign the new target device the blank disk.

Right click the target device and click “Set Device as Template”

Right click the new device collection and click “Auto-Add Wizard…”

Complete the auto-add wizard

Now you can try it out.  Create a virtual machine, set it to boot from the network and start the virtual machine.

Check the default collection and you’ll see the new device.

Rename the target device, create the active directory account, move the target device to it’s permanent device collection and reboot.