A7 (NG) MFD reboots when connect to SeaTalk Network

[Mickstr6]

Last question until I get back to the boat. If I disconnect the power currently supplying the Sea Talk legacy network, is power to the NG network available from the A7 MFD power source to power everything? I thought that the separate power to the A7 was required, as power to the MFD was not supplied via the network.
I'm wondering if I don't enable the breaker for the legacy Sea Talk, will power from the MFD be available through the MFD network connector to power the EV-100 P70 head, and through the Sea Talk to NG converter also power the Sea Talk instruments?
Or, do I need to add a new power source to the NG network, and not use the power source from the old Sea Talk network?
(Hope this all makes sense..)