I built a pc with a i3 9100f and asrock b365 mobo and 2x4 gb viper ddr4 ram. When 1 ram stick is installed in any slot, the pc boots. When i have 2 ram sticks installed, it doesnt boot, no matter what slots they are in. I already returned the mobo and got a new one and it still does it. I have tried clearing cmos, updating bios, i checked the cpu and it doesnt look messed up on the bottom or anything. Is my cpu probably the issue, or could it be something else?