Re: noise. Or the lack of it.
A much smaller DEC, in a filing-cabinet-sized rack, was installed in an attorney's (barrister's) office suite. This was a new business series intended for such uses. The fans were quite effective at keeping it running, but did not fit in with the character of the surroundings. Normal abatement efforts were unsuccessful, so the senior attorney contacted an executive at DEC. The executive, oddly enough, went down to the shop floor, listened to an example of the unit in question, and replied "That's unacceptable. I'll have a tech there to replace them with quieter fans very soon."
In the fullness of time, a tech with a couple of brown boxes appears and installation of said new fans begins. Unfortunately, a Murphy demon also arrived and a wire slipped from its usual place to brush the CPU board. The other end of the wire, as you have guessed, carried voltage and currents suitable for destroying business computers. Imagine upsetting sound effects and smells. The Murphy demon's friends in the DEC warehouse then hid all the matching CPU boards so what had been a nice bit of slightly-noisy kit remained expensively silent until a distant assembly line came round to building that board again.
The secretaries transcribing dictation tapes appreciated the quiet, at least.