Every watt a processor spends computing comes back out as heat, and if you cannot carry that heat away fast enough, the chip does the only thing physics allows: it slows itself down, or it dies. This is the constraint nobody puts on the slide. Clock speeds, core counts, model sizes, all of them are ultimately arguments with a temperature, and the people who win those arguments work in a discipline most of the industry never names. Their tools are stranger than they look. Vapour chambers that boil a working fluid to whisk heat sideways across a surface, thermal interface materials engineered almost atom by atom to bridge the microscopic gap between a chip and its cooler, and increasingly exotic substrates chosen for how eagerly they let heat pass through. The insight beneath all of it is a change of verb: heat is not something you resist and endure, but something you route, and whoever routes it best sets the speed limit for everyone else.