TDP (Thermal Design Power)
TDP is the amount of heat, in watts, that a component's cooler must be able to remove. It is a cooling specification, not a precise power-draw figure.
TDP exists to tell cooler designers how much thermal load to plan for. A 120W TDP CPU needs a cooler capable of dissipating roughly that much heat under sustained load.
It is frequently read as power consumption, which is close but not exact. Modern processors can briefly draw well above their TDP during boost, and manufacturers do not all define the figure identically.
For sizing a power supply, TDP is a reasonable starting estimate but not a substitute for the manufacturer's stated power requirements — especially for graphics cards, where transient spikes exceed the nominal figure.
Where this decision gets made
CPU Coolers buying guide →
Turn it into a real number
PC Electricity Cost Calculator →