If that had been true, then I guess there would be no offerings of "workstations" that pack server-grade CPUs into the tower cases ready to be used as more powe

If that had been true, then I guess there would be no offerings of "workstations" that pack server-grade CPUs into the tower cases ready to be used as more powerful desktop machines. I happen to have one at home (dual socket) and it's silent just as a regular machine. Noise that we find in server machines is because of the fans pushing loads of air basically out through the 1U/2U tunnel. With tower cases that is not the case and hence there's no noise.