PC no longer working with CPU at stock/auto speeds. Troubleshooting CPU or mobo?
I've got an issue that appeared out of the blue on my year-and-a-half old system:
On starting the PC up in the morning, I suddenly got no video out. Tried another, lower powered GPU but still no video out. I downloaded the latest BIOS and flashed the motherboard. That has gotten me display out so I could access the BIOS, but as soon as it has loaded the boot drive, the EZ debug LED on the motherboard flashes briefly for CPU and the PC reboots immediately. I've tried this with all peripherals unplugged and the weaker GPU connected, so I don't think it's a PSU issue (but I've got no other to test with). Have re-seated/shuffled RAM and re-seated CPU.
Some googling led me to try underclocking and undervolting the CPU. That lets me boot into Windows and I promptly updated the chipset drivers (did not fix the issue). Using Ryzen Master I tried a few clock speeds and voltage combinations. I did manage to clock back to the advertised stock speed of the processor while undervolting (no PBO), but it's not stable. (Also tried a fresh Windows install but no luck) Currently stable at 3 GHz @ 1.3v
So that's the jam I'm in. I suspect it's either the CPU or the motherboard. Is there a way for me to narrow down the troubleshooting further to figure out which is the most likely culprit without running out and buying new components?
System details:MSI B450m Mortar Max, Ryzen 3700x, 2x 16GB Corsair CMK32GX4M2E3200C16, MSI RX 5700 XT Gaming X, EVGA 850 G3, and some SSDs and hard drives.
Update: Clocked back to stock with a small voltage offset and boost disabled, but it still shuts down with a BSOD occasionally. Would greatly appreciate some pointers.
