My PC was working normally until today, when the display stopped waking from sleep. Moving the mouse and pressing keys did nothing, so I held the power button to shut it down. Since then, it will not start properly.
I've power-cycled the PSU and wall plug, tried different HDMI connections from both the graphics card and the CPU's integrated graphics, unplugged the system and discharged it by holding the power button, and cleared the CMOS. The motherboard's CPU debug LED stays solid red, while the DRAM, VGA, and storage LEDs remain off.
The system was built in April 2025 and had been stable until this happened. The parts are:
- AMD Ryzen 9 9950X3D
- ASRock B850 Steel Legend WiFi
- XFX Mercury Radeon RX 9070 XT
- Corsair Vengeance DDR5 64GB (2x32GB), 5200MHz CL40
- Corsair RM1000e 1000W power supply
- Samsung 990 Pro 2TB PCIe 4.0 NVMe SSD
There have been reports of processor failures involving some ASRock boards, but I'd like to do as much troubleshooting as possible before considering an RMA. What should I test next?
2 Answers
Try booting with only one RAM module installed. Remove both sticks, install one in the motherboard’s recommended single-stick slot, and test whether the system reaches POST. If it fails, move that same module through the other slots, then repeat the process with the second module. This can rule out a memory module or DIMM-slot problem even if the DRAM debug light is not currently on.
The fault is most likely either the CPU or the motherboard. If you can borrow a compatible processor or board, swapping one component at a time is the clearest way to identify which part has failed. A compatibility problem alone seems unlikely because the system worked for months; an incompatible BIOS normally would have prevented it from booting from the beginning.
I don’t have a spare CPU or motherboard to test with. I was referring to reports of processors failing while used with some ASRock boards, rather than a basic compatibility problem.
Would this still be worth trying when the DRAM debug LED is off and only the CPU LED is lit?