@raccoon If this is a first build, make sure all packaging and protective stuff is removed between the cpu and the heat sink; should only be a little square of gunk that came on the heatsink, or a small dab of thermal paste you put on yourself
try it disconnected from the case, like sitting on the cardboard box the mobo came in. nothing conductive!
leave an offering of food out overnight to entice shoemaker elves to visit and fix it for you
different power supply?