died-dies will go up'n'running after a few restarts and a few tries with their own specific voltage on the settings... just play around with the voltage until they will come back to life, each one is also physically different for several reasons so, very probably you wouldn't find a precise "value" that will fit them all...

On the more, try to cut the exceeding thermal pads on the top of the VRMs if not totally substitute them with something more efficient... you can check the KnC hardware thread on this Forum and go back to the period when the firsts Neptunes were delivered (june-july 2014) to find some really good advices and a lot of pictures and examples too...

Good Luck!  


Regards,
up.debug