Hey everyone, I could really use some assistance. I built my own PC, using a 7800X3D CPU and an MSI MAG B650 Tomahawk WIFI motherboard, but it's not powering on at all. When I press the power button, nothing happens. I've tried powering it on without the CPU power cable connected, and two lights on the motherboard's EZ Debug are showing 'CPU not detected' and 'RAM not detected'. I've reseated the CPU and checked the socket for bent pins, but everything looks fine. I've also moved the RAM sticks around, trying both configurations, but still got the same lights. The motherboard's serial number shows it was made in February 2025, so it should support the CPU. I'm out of ideas and don't have another PC for troubleshooting. Any thoughts on what I can try next?
2 Answers
Definitely connect the CPU power cable because it won't boot without it. Have you tried updating the BIOS using the BIOS flash button? Also, remove the GPU and try booting from the motherboard's video port. What RAM are you using?
You need to make sure that the CPU power cable is plugged in for the system to boot up properly. Have you been using the case's power button and not just flipping the PSU switch?
I’m using the front button on the case. When I press it without the CPU power cable connected, the CPU fan starts and the GPU's RGB lights up. But when I plug in the CPU power cable, nothing happens.
I have 2x 24GB Corsair Vengeance DDR5 6000. I’ll give booting without the GPU a shot.