CoolTech Fan Technology
ASUS R&D has created an entirely new fan design, dubbed CoolTech, to more efficiently use air flow, so the fan speed (and thus, noise) can be reduced while still reaching the same level of cooling.
The blade design is two-stage. The inner radial blade sucks air inwards and blows it out towards the curved, downward facing outer blades. Compared to a traditional, single curved fan blades which blow air out in all directions, the new CoolTech design forces more air downwards so it spends more time in the heatsink collecting heat. The effect is clearly shown in the video below as the rice grains are moved very quickly and easily.