Droid DNA, keeps restarting

[AC Question]

My DNA keeps restarting, it doesn't even go to the home screen for me to shut it down...let alone when I hold the power button and the volume button it doesn't stay on the screen long enough for me to do a factory restart. I went ahead and swapped out the motherboard, the battery and the charging port area. Still didn't fix it, it's still restarting itself over and over and over again. It doesn't show the charging light when plugged into the wall charger, it won't even turn on and do the whole retsarting thing unless it is on the charger. What is the problem? what do I do now? HELP!