Question about ASUS Prime Z390-P

Hello all, I have had a computer with this mainboard for quite some time. Now my computer just went out a few days ago and I can no longer start it. I plugged in all the slots again, changed the battery, tried to start the computer without the graphics card, but it didn't work. When I turn on the power, the slots of the graphics cards light up yellow. However, I can rule out damage to the graphics card because it doesn't work without one either. My guess now is a defective motherboard or power supply. Can anyone possibly help me?