According to the drawings below, Apple wants to introduce the upcoming MacBook’s a ventilation system through USB port and Firewire. Obviously, the venting will not happen just through those portals but also through traditional paths.
The idea itself is not bad because good ventilation forbids over-heating components, but the effectiveness depends on the number of peripherals with interface USB or Firewire it uses. It is logical that when holding one or more portals, the control system will stop venting on those routes.
This is one of the methods proposed by Apple engineers to improve the cooling system. Other projects related to the introduction of sensors to detect air flow power in order to adjust it depending on the temperature of components or introduction some elements which take the heat generated by components and transfer it to a secondary chassis, designed to dissipate heat more efficiently.
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