from electro mechanical sensor elements fig1 shows non limiting logic in accordance with present principles at block 36 a motherboard is engaged with a chassis and at block 38 the form factor unique chassis structure is detected by means of the sensor elements on the motherboard interacting with the form factor unique chassis structure the sensor elements provide a signal functionally a form factor identification to the motherboard cpu which may e g execute bios to look up or otherwise correlate the signal to one or more parameters at block 40 the parameter s are established at block 42 typically by the cpu non limiting examples of parameters that are established include chassis fan speed and activation or use of a particular type of input output structure and or protocol fig3 shows an example non limiting implementation in which electro mechanical sensor elements on the motherboard 12 are established by electrically conductive contact pads 44 that can be aligned with each other in one flat dimension of the motherboard looking down on fig3 the y dimension as shown and offset from each other in the other flat dimension looking down on fig3 the x dimension each pad 44 is connected to a voltage source 46 through a respective resistor 48 also each pad 44 is connected to a.