Case fans

[xBlueXFoxx]

You dont need a vacuum effect...you need flow. Vacuum would mean all the air gets sucked out which would create a very low flow and no constant cool air intake. As for efficiency, it means having enough Flow to keep the processor within certain temperature limits, overdimensioning on flow means you will use too much energy and noise. Infact, having too much fans is Bad for your computer since it will suck in excessive air and therefore have a faster dust buildup which creates an isolating layer around your pc parts. Since heat diffusion is passive it is way more inefficient than convective systems.

I mean a vacuum effect as in you want it to intake air from one side and blow it out on the other, aka airflow. You must not have understood what I meant clearly.