I didn't realize that I had three topics on the matter,.. but alas - there they are:
Speculative Theory: SSD causes System power cycle
Windows Update: Rogue Reboot
CPU Temp
But I think I have maybe finally come down with the probable cause... I think.
This box runs a AMD A10-6800k Chip - and had a stock cooler on it. I found a thread via I believe it was Tom's Hardware that mentioned that the stock cooler wasn't enough.
The system was pushing high temp - 150-180F and if I was really pushing the system - would be more like 200-220F. I wonder now if it wasn't hitting thermal limits and power cycling to prevent 'heavy' damage.
Well - Enter the GeminII S524 ver.2 Cooler.. Holy cow,.. it is about 4x the surface area as the original and have five heat pipes...
Maybe - just maybe... the issue is now really solved.... likely I should look at replacing the chip since it's had such a thermal cycling...
Comparison 1
Comparison 2
Stock Cooler
GeninI