To my knowledge there is no hard-wired physical thermal shutdown. That would be some kind of thermal fuse/breaker. There is a sensor on the processor. When it hits a certain threshold the processor will shut down which in turn shuts down the server. The preset temperature that shutdown occurs is programmed into the CPU. I'm not sure what the exact temperature is that a shutdown will occur, but it is quite high. Modern computer components can sustain much higher temperatures than their predecessors.
Our management software will start giving thermal warnings at around 130-150F. The latest Xeon processors have a listed maximum temperature of around 200F.
Dell EMC, Enterprise Engineer
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