I'm facing an issue with my PC that I need help troubleshooting. Here are my specs: MSI B550 A Pro motherboard, AMD Ryzen 9 5950X CPU, EVGA XC3 RTX 3090 GPU, Samsung 980 Pro SSD, and a Corsair RM1000x 1000W power supply. I recently moved, and before that, I had encountered this solid white CPU debug light a few times. Typically, reseating components would solve it, but after moving, I'm stuck with this problem and cannot get it to boot. I've tested my setup with a functioning 5800X CPU, and I'm still getting the same issue, so I'm pretty sure the CPU isn't the problem. Everything powers up, but I can't get any video output because it gets stuck at the CPU light. Could this be a faulty motherboard, or is my power supply failing? Are there other things I should check to help narrow down the issue?
3 Answers
Just to clarify, you've tested the motherboard with a 5800X and it still had the same issue, right? That could indicate a problem with the motherboard itself, especially since you mentioned the old setup worked fine.
Since you've ruled out the CPU, I would suggest first checking all your power connections – make sure everything is snug and connected correctly. Sometimes during moves, things can get a little loose or disconnected. If you have access to another PSU, trying that could also help you determine whether it's a power supply issue or not.
It sounds like it could indeed be a PSU problem, especially since you mentioned it spins up but doesn't boot. If reseating components doesn’t work, I’d consider testing with another power supply if possible. Those symptoms can sometimes lead to a motherboard problem, but the fact that everything powers on is a good sign.

Yeah, exactly! The 5800X came from a working rig, and it still didn’t boot up on my setup.