I just upgraded from an 8-channel NVR (DS-7608NXI-I2/8P/S, 4.62 firmware, 8-PoE) to a 16-channel one (DS-7616NXI-I2/16P/S, 5.03.010, 240606 firmware, 16-PoE).
With the 8-ch NVR is was able to add cameras from my network by switching from Plug-and-Play to Manual, I wasn't using any of the PoE...