My PC froze completely while I was watching a movie, so I held the power button to shut it down. Since then, it powers on with the fans spinning but never shows an image or completes POST.
The system has a Ryzen 9 7900X3D, an ASUS Prime B650-PLUS WIFI motherboard, an XFX Radeon RX 7900 XTX, two 32GB DDR5 sticks, and a Corsair RM850x PSU. It was built in February 2024.
I left the PSU switched off and unplugged overnight, removed the graphics card and tried both motherboard video outputs, tested every RAM configuration including no RAM, cleared the CMOS using both the CLRTC pins and battery removal, and tried running the board outside the case with only the CPU installed. The fans still spin, but there is no display or obvious restart cycle. This motherboard doesn't appear to have traditional POST diagnostic LEDs or a speaker.
What else can I check to determine whether the PSU, motherboard, CPU, or another component failed?
2 Answers
Keep the setup as minimal as possible: motherboard on a nonconductive surface, CPU and cooler installed, one memory stick in the recommended slot, and no drives, USB devices, or expansion cards. After clearing CMOS, give an AM5 system several minutes for memory training before forcing it off. If it still fails with known-good power and minimal hardware, the motherboard or CPU becomes much more likely than the GPU.
Start by checking the motherboard’s diagnostic behavior. ASUS lists a feature called Q-LED Core for this board, which uses the case power LED to indicate whether the CPU, memory, graphics, or boot device is preventing POST. Follow ASUS’s instructions carefully and observe the LED’s blink pattern. That should narrow down the failing stage even though the board lacks the usual onboard Q-LED indicators.
I had missed Q-LED Core because I was looking for physical diagnostic LEDs. I’ll check the board’s power-button LED behavior using the ASUS procedure.