From your diagnostics, you're running a 10th Gen Intel (10400)
There's a quirk with the motherboards for the 10th Gen where the motherboard manufacturers all decided to effectively do a significant overclock on the CPUs out of the box without any user intervention.
Namely, they would set the TDP of the CPUs to be "Auto", and instead of setting it to TDP of the CPU installed (what you would think it would do), auto in this case meant unlimited or 4096 Watts. In your case, the CPU is 65Watt.
The rather extreme auto setting that the motherboard is using has the effect of an overclock because it overrides the internal settings on single core turbo boost, effectively allowing all 12 cores to run full tilt all the time with no regard to the temperatures internally. Even with the best cooling available this has the effect of introducing big instability into any system.
See this post https://forums.unraid.net/topic/100360-z490-multi-core-enhancement/#comment-926134, watch the video and then change the TDP within the BIOS to 65Watt. Limetech support has seen this issue several times. All Overclocks introduce instability.