computer makes high pitched noise when turned on

It’s an approach that works even with years-old video cards such as a GeFore 4 MX onboard video. This bypasses the monitor’s electronic control circuit, which can be left at maximum brightness, thus eliminating the noise. Using this control reduces the brightness in the video card output. The color adjustment screen in the display characteristics control panel also provides a brightness setting. Thankfully, there is a simple workaround within the software controls bundled with most video card drivers. To modify this electronic circuit in order to reduce or eliminate the whining noise is an impossible challenge for most users. A similar effect may be happening with the monitor CFL bulbs.

For example, while it allows a fan to start reliably at unusually low speed, an improperly matched PWM control circuit can cause a DC fan to emit more clicking, buzzing and chattering noise as it is slowed. Most likely, this is some form of PWM (pulse width modulation) circuit, a very useful tool that, alas, can have negative side effects. The source of the problem appears to be components in the electronic circuit which controls the brightness of the CFL bulb that lights most LCD monitors. If you’ve spent the time and effort to study the information on SPCR and managed to achieve super-quiet performance in your computer, this whine can be absolutely frustrating. It can be piercing and annoying enough to overcome even relatively high ambient noise. The noise usually gets worse the more the screen is dimmed. That’s when the monitor can start to emit some high frequency tones, which are described most often as buzzing or whining. The natural response is to turn the brightness down using the monitor’s controls. Usually, it does not occur when the monitor is set to full brightness, which is usually too bright for most users.

Many computer users have run into the issue of whining LCD monitors. Also, please participate in our Quiet / Noisy Monitor Survey! Here’s a simple workaround that can work quite well with most monitors for many users. The high pitched noise from many LCD monitors when their brightness is reduced can be utterly distracting.

Computer makes high pitched noise when turned on