Thus, the Athlon XP 3200+ with its Barton core has the highest maximum thermal power of 76.8 watts. But as it has a 20% larger die surface than the Thoroughbred B Core, on which the Athlon XP 2600+ and the XP 2700+ are based, its maximum specific thermal power is more than 5 watts lower at 76 W/cm² (about 7%).

However, a lower specific thermal power means that an XP 3200+ is also easier to cool. Or, put another way, coolers that can keep the die temperature of an Athlon XP 2700+ under control will not have any problems with a 3200+ CPU.

An oversimplified equation that describes the cooling performance - or the flow of heat through a cooler - explains this paradox:

Iw = G*(TD-TA ) where G=λ* (A/l)

where

Iw : heat flux

G: heat conductance
λ: thermal conductivity of the cooling material
A: area through which heat flows (contact surface between the die and cooler)
l: distance traversed by the heat flux
TD: maximum permissible die temperature according to specifications
TA: temperature in the vicinity of the ventilator

Thus, the larger the contact surface between the cooler and the die, the greater the heat flow through the cooler.

The following illustration provides an overview of the maximum specific thermal power of the various Athlon XP cores.

Specific thermal power of the various AMD cores