This was my first time building a PC so I don't have much insight on whats going on but I believe it's a faulty stick of RAM. I bought a 16gb pair of G.SKiLL ram sticks with 8gb on each, when both sticks are inserted it won't boot. I'm using the correct slots on the Mobo (ASUS h170) according to the manual. It will boot with RAM stick A in the first slot, although when I stick RAM stick B in the first slot it won't boot at all. That makes me believe it's the RAM stick but since this is my first time building I wasn't sure if there was something in the BIOS that needed to be changed or if I'm doing something wrong.