Diagnosis
A high-frequency electrical noise, often called coil whine, is originating from the monitor's internal power supply or circuitry.
How to Fix It
First, isolate the source. Power on the monitor with no video cable connected. If the whine persists, it is internal. Try a different, grounded power outlet on a separate circuit. Electrical noise on the line can excite the components. Adjust the monitor's brightness. Coil whine often changes pitch or intensity with load; set brightness to 70% or 30% to see if it diminishes.
If That Didn't Work
The whine may be related to a specific refresh rate. In your graphics driver control panel, temporarily change the refresh rate from 144Hz to 120Hz or 60Hz. Test for noise reduction at each setting.
Heads Up
Minor coil whine is a common characteristic of many electronic devices and is not typically indicative of imminent failure. However, if the noise is loud, changes to a popping or cracking sound, or is accompanied by visual artifacts, contact ViewSonic support.