Re: I used to think 'the clearner' was urban myth...
"Modern switching supplies"
There was a time before modern switching supplies were used. We had to make do with mains transformers, rectifiers & big electrolytics. And BTW big electros intended to sit upright with wires connected to their terminals don't necessarily take kindly to being mounted upside down on motherboards supported only by the terminals.
I've seen a Z8000 server sitting in a room next to the lift being reset by its neighbour. Also a Z80 (the one with the humungous upside down caps) being reset when the stabilised xenon microscope illuminator was fired up.