Lenovo brand monitors have an on-screen display (OSD) that is used to administer basic hardware level changes such as brightness and contrast. The OSD appears the same no matter the settings of the monitor, so if a change has been made that crippled the display, the monitor's OSD can be reset to the factory defaults. The buttons for navigating the OSD are located on the front of most Lenovo monitors. While the reset process may differ slightly on some Lenovo monitors, the majority will be identical or extremely similar in construction.
Press the power button to turn off the monitor.
Press and hold the menu button. The menu button is marked by a rectangle with an arrow pointing to the right.
Press the power switch to turn on the monitor.
Wait while the power light cycles between green and amber, then release the menu button.