Cpu Motherboard No Display - Simulating VPP Voltage #cpu #display #blackscreen #ram

追加: 2026-06-03

[00:00:00]This PC turns on, but there's no display. After checking, I found that the RAM's VPP voltage is missing. Let's take a closer look. This PL7 is the circuit that supplies the RAM's VPP voltage. As you can see here, the voltage is only 0.08 volt. And here is the VIN voltage for the MP1475 IC currently measuring at 5 V. And here the voltage for the enable pin reads 4.5 volts. But the IC is still not working.

[00:00:32]I think this IC is faulty. But before we replace it, let's simulate the VPP voltage using a bench power supply. So I'm going to inject 2.5 volts right here. And let's power on the motherboard. As you can see on the power supply, the current is starting to ramp up. And there we go. We got a picture on the