Estrobeda :
I can specify my question little more. Today you can build a own all-in-one pc's with thin-mini-itx motherboards. You will need a all in one barebone which will come with cpu fan and a built in display. My goal with this question is to find out if you can take the display from a regular monitor and replace the built in one?
An 'all in one' is basically a laptop in a different configuration. All in ones (or laptops) generally have an output port for a secondary monitor. I suppose you could tap into that, and provide signal to a regular monitor.
But a regular monitor would also need its own power supply.
And would not provide a better or worse picture than the original screen.