How to change the background color (from the default white color) when viewing files in the 3D view?
Proceed as follows:
Go to Options > Defaults...
In the Defaults window, scroll down to Start up defaults and expand it.
Double click 3D View Mode.
In the 3D View Mode window, under the Background color section, uncheck the Windows default option.
Set the desired color for the background by either entering the Red, Green and Blue values or by selecting the color from Select Color... option.
Click the OK button.
Save the changes made to the Defaults in the Defaults window. For more information, please click here.
When you create a new 3D file, the background color will be changed to the new color that has been set.
When working in a server and client configuration, make sure to save the changes as "Shared Defaults" by doing a "Save As" in the Defaults window. Failing this, the defined color will be set as the background color only for that user and not for all users.