My system suddenly stopped booting. The ASRock B850M Pro RS WiFi powers on and its RGB lighting works, but there is no display, no BIOS access, and my keyboard does not light up. The motherboard's green POST indicator stays solid, which the manual says points to a boot-device problem.
I removed the boot drive, graphics card, and other storage devices, then connected the monitor to the motherboard's DisplayPort output, but the behavior did not change. I also shorted the CMOS-clear pins and performed a BIOS Flashback, apparently successfully, but the system still will not POST.
I built this system before hearing reports about some newer boards damaging Ryzen 9000-series processors. Since I'm using a Ryzen 7 7800X3D, I'm unsure whether the CPU could still be affected. I don't currently have another compatible motherboard or processor available for testing. What should I check next, and is the board more likely to be faulty than the CPU?
2 Answers
Make sure the BIOS Flashback actually installed the newest firmware for the exact board revision. A recent BIOS update includes newer AGESA changes, improved memory compatibility, and a fix for boot failures with certain CPUs. Since the Flashback process completed, try clearing CMOS again afterward and booting with only the CPU, cooler, one RAM stick, and the power supply connected.
The most useful next step is isolating the hardware. Power it down, remove the RAM completely, and try starting it to see whether the diagnostic behavior changes. Then test with one memory stick at a time in the recommended slot, reseat the CPU and power cables, and inspect the socket for bent pins. Without another compatible board or CPU, there’s no reliable way to tell whether the motherboard or processor failed.
Should I remove all the RAM first, or just test with one stick? I’m also considering replacing the board with a model from another manufacturer.
I used the latest BIOS available for the board. The Flashback light blinked slowly, then faster, then rapidly, and finally turned off, so the update appeared to complete normally.