Well, the physical CPUs are also subject to various non-deterministic manufacturing variations. As long as you stay within the recommended frequency/voltage/temperature limits, everything is fine. Once you are past these limits, nothing is certain.
With all the overclocking going on with Ryzen/Threadripper CPUs, I wouldn't be surprised if some "lucky" guy pushed his CPU just slightly over its physical limits, where the system is still stable most of the time, but the floating point calculations sometimes do give incorrect results.