I built a new PC with a Gigabyte Z370p D3 mobo i7 9700k and 1080. But every time I play a game the pc locks up(freezes) even though all the fans are still on, so I thought my PSU was the problem so I brought an 850w EVGA PSU and installed it but the PC still freezes so my PSU isn't the problem and I did a fresh install of windows so that isn't the problem either. Please, someone, help me is it a faulty mobo or CPU? As just want to use my new parts.