Oh, sorry for not making that clearer. I recorded myself humming at the pitch I was hearing and recorded the noise itself by positioning the microphone at the source of the noise (top ventilation grate, center). I got consistent results for both so I presumed it was measured reasonably well. I guess...

Dell U2410 Tests conducted by ear, 1 m from the monitor, in a reasonably quiet environment, sitting about 0.7 m away from the screen. At 100 % brightness, monitor is completely silent 99-76 %, virtually inaudible, but on this monitor 76 % with 50 % contrast is really quite bright 76-50 % the buzz/h...