The Power Mac G5 is the world’s coolest personal computer
 

Liquid Cool - Dual Processor

Mind-boggling leaps in processing power require innovative design for dissipating heat. So the Power Mac G5 delivers a system that screams with power, not noisy fans.

Hip To Be Cool
Take it up a notch without losing your cool. The top-of-the-line Power Mac G5 with dual 2.5GHz processors squeezes outrageous performance into tight quarters. To cool down those steaming circuits, Apple designed a sophisticated liquid cooling system that takes off the heat without bumping up the noise. Mac OS X dynamically adjusts the flow of the fluid and the speed of the fans based on temperature.


The dual 2.5GHz Power Mac G5 features an innovative liquid cooling system that’s more efficient than a traditional heat sink. This system provides a continuous flow of thermally conductive fluid that transfers heat from the processors as they work harder. The heated fluid then flows through a radiant grille, where air passing over cooling fins returns the fluid to its original temperature.

Truly Intelligent Design
An exceptional computer demands an exceptional enclosure. The Power Mac G5 has a stunning chassis forged of anodized aluminum. Apple engineers were also pretty obsessive about clutter. That’s why there isn’t any. Especially conspicuous by its absence is that tangle of unsightly wires and cables that turn the inside of a typical PC into a veritable rat’s nest. “A place for everything and everything in its place” isn’t just something your mom said: It’s an important philosophical precept that Apple applies rigorously to hardware design.

This clutter-free design also allows for intelligently managed heat dissipation through four independently controlled thermal zones. To make the Power Mac G5 even easier to cool, a transparent internal air deflector channels airflow over the processor heat sinks and the expansion slots.


It’s no secret that computers generate heat. So Apple divided the inside of the Power Mac G5 into four discrete thermal zones, compartmentalizing the primary heat-producing components — processor, PCI, storage and power supply. So the system can decrease the temperature of a single zone without affecting the others.


Each of the four thermal zones is equipped with its own dedicated, low-speed fans. Apple engineered the nine fans to spin at very low speeds for minimum acoustic output. Using 21 different sensors, Mac OS X constantly monitors component temperatures in each zone, dynamically adjusting individual fan speeds to the appropriate levels for the quietest possible operation. As a result, the Power Mac G5 runs two times quieter than the previous Power Mac G4 enclosure

http://www.apple.com/powermac/design.html

I would love to check out the case design incorporating some neat air flow scheme.