Monitor makes a buzzing or high-pitched noise

Symptoms

• Faint high-pitched whine or buzz coming from the monitor
• Noise changes with brightness level or content on screen
• Noise is more noticeable in a quiet room
• No noise from speakers, just the monitor housing itself

Likely causes

• CommonCoil whine from the internal power supply or backlight driverSmall electronic components can vibrate audibly at certain power loads, especially at specific brightness levels.
• CommonPWM backlight dimming creating an audible frequencySome monitors use pulse-width modulation to dim the backlight, which can produce a faint whine at lower brightness.
• PossibleFailing or aging capacitorA capacitor nearing failure can sometimes buzz more noticeably before other symptoms appear.
• Less commonLoose internal component vibratingA rattle or buzz that changes with the monitor's physical position can indicate something loose inside.

What to do

1. Note whether the noise changes when you adjust brightness up and down, which points to backlight-related whine.
2. Try a different brightness level, since PWM-related whine is often worse at lower brightness settings.
3. Move the monitor slightly and listen for changes, which can suggest a loose internal part versus a fixed electronic hum.
4. Compare noise level in a quiet room versus with background sound, since some coil whine is inaudible except in silence.
5. If the whine is faint and doesn't change with tilting or moving the monitor, it's most likely a harmless coil whine common to many monitors.
6. If the noise is loud, gets worse over time, or is accompanied by a burning smell, unplug the monitor immediately and stop using it.

Tools and parts

• None

When to call a pro

If the noise is loud, worsening, or paired with any smell of burning, have a technician inspect the internal power supply rather than continuing to use it.

Safety