Change the number of colors displayed on a monitor

Open Display in Control Panel.
On the Settings tab, if you are using multiple monitors, click the monitor icon that represents the monitor that you want to adjust.
In the Colors list, click a color setting.

note Note

To open a Control Panel item, click Start, point to Settings, click Control Panel, and then double-click the appropriate icon.
A High Color setting will display over 65,000 colors. A True Color setting will allow over 16 million colors.
Settings that display a large number of colors require a significant amount of your computer's processor resources.
Your monitor and display adapter determine the maximum number of colors that can appear on your screen.
If you are using multiple monitors and you click the icon for a secondary monitor, the Extend my Windows desktop onto this monitor check box must be selected to change the settings for that monitor. You can specify the color settings for each installed monitor.