Abstract: EMI from an operating information handling system is managed by disposing a stirring device in the chassis of the information handling system to mechanically modulate the resonance of predetermined RF signals emitted from processing components within the chassis. For example, a cooling fan disposed in the chassis has a reflective surface formed on its blades so that rotation of the blades mechanically modulates the RF signals. The blades have a depth of at least one-quarter of the wavelength of the RF signal and are coated with a low resistance material, such as steel, aluminum, copper, carbon loaded plastic or a high dielectric ceramic. The fan rotates at the faster of the speed required to provide desired cooling or the speed desired to produce a desired average RF signal amplitude.

Abstract: A portable computer system is disclosed comprising a central processing unit, a keyboard input unit coupled with the central processing unit, a display system coupled with the central processing unit, means to turn the display system on and off, wherein normal operation of the keyboard does not turn the screen on once the display is turned off.

Abstract: A portable computer system is disclosed comprising a central processing unit, a keyboard input unit coupled with the central processing unit, a display system coupled with the central processing unit, means to turn the display system on and off, wherein normal operation of the keyboard does not turn the screen on once the display is turned off.