Question Everything stopped working but PC seems fine. Red light on MOBO. Display and usbs wont work.


Feb 5, 2019

I ran into a really strange problem and i dont know how to fix it. My PC was working fine and suddenly the screen freezes. So i turn it off by holding the power button. When i turn it on again the display and all peripherals wont work (keyboard, mouse, not even rgb lighting on mouse or keyboard lights up). The disk light on the case (nzxt) also doesnt lights up or flashes.

So my first guess was the motherboard. Thats why i took apart the components one by one. Nothing! I was only left with the motherboard connected to power supply and also nothing. Not even the light on the mouse. So i thought it was the motherboard.

Today i bought a new motherboard just to see if the new motherboard will do the trick (Aorus elite b450). I connected everything and boom, nothing. No disk light on the case, no display signal, no power in keyboard, mouse...Then i noticed that the vga red light is on the motherboard. When i turn on the pc red light on vram flashes, it flashes on cpu and then the vga red light stays on. its the gpu? Maybe not. I disconnect the gpu from motherboard, and the PSU and still the red light is on for vga and problem has not been solved...I took out the ssd and hdd...nothing, i took out ram one by one...nothing...The only thing i didnt took out was the cpu, can it be the cpu?? even with the vga red light? and why the usb ports are not working even on the new motherboard....

So i can now guess if its the PSU or CPU? but all the lights turn on in the case, all fans are working (even on the gpu) so i guess the PSU is not the problem....

Any ideas?

I am running:
Ryzen 2700x
RTX 2070
16gb RAM Corsair Vengence PRO
ASUS x470 prime motherboard -> now B450 AORUS ELITE
750W PSU Corsair TX750M
Oct 2, 2020
I think that could be CPU because the PSU ,I think, Would not even allow the motherboard to work if it was faulty in some way. So if there is a AM4 compatible processor you can get then try that.