Samsung Galaxy S3 suddenly dies and won't turn on even after battery removal The phone was plugged in to my computer (I was doing development) and was running all the time. Suddenly, while I was not doing development or doing anything, the phone died and I have have never been able to turn it on again.  

I've tried:


Hold the Power button
Hold both Power and Volume down button
Take out the battery and put it in again
Replace the batter with another one from my friends' working-perfectly-fine Galaxy S3  


The result is the same: no response from the phone at all - it's completely cold, no sound, light or vibration at all - all I've seen is the blank unchanged screen so please don't ask me about the start up screen

What can I do?
I have found out through searches that this is the Sudden Death Syndrome (SDS) which many have reported especially for Samsung Galaxy S3.  

It was the motherboard that was broken and replacing it brought the phone back to life.