Auto Adjust is the automatic display synchronization by means of the incoming video signal. Frequency (no vertical stripes), phase (no faint screen distortions) and picture position.
Many multi frequency monitors handle certain video modes incorrectly. It can often be noticed that the picture on the screen is not displayed accurately in size or centering as long as the signal is not being saved. Auto Adjust allows for an automatic calculation and setting of screen size followed by positioning it using the microprocessor. These adjustments can be triggered by pushing a button on the front side of the monitor or using the OSD. This function is not necessary for digital input signals and therefore is not available when the display is connected to the digital graphics port.
Today, there is basically no more flat screen that would lack an Auto Adjust function for frequency, phase and picture position. But Auto Adjust doesn't always work the same way in all devices. A good LCD reliably manages the synchronization at the push of a button and independently from the utilized graphics card. It is especially convenient if the adjustment is performed fully automatic at every change in frequency or resolution.
And yet, the Auto Adjust function can have some drawbacks, namely if it's not limited to adjusting frequency, phase and picture position. Some cheap devices happen to co-regulate contrast or brightness at the same time whenever the button is pushed. The default brightness and contrast settings that LCD monitors set during the auto adjustment are seldom chosen ergonomically. Pictures might seem impressive at first when having the LCD at a luminance of 180 cd/ m² shown to oneself in the shop, but at home, one will surely get red eyes or headaches after a while. Regular values for work places are values of 70 to 130 cd/ m² depending on the environment's lighting conditions and personal preferences.