@stefano About 15 years ago, the place I worked had a supercomputer. One night, the aircon in the machine room failed. The machine kept computing, and the temperature rose. It rose *quite a lot*.
Sadly, the first thing to fail from the heat was the core switch for the room. You know, the one that handles all of the network for everything in the room. Including the temperature alerts.
It was finally spotted about 8am when the security patrol wondered why the door shutters were so hot.