Many years ago, programs started using splash screens to give you something to look at while the program was loading. Now days many programs load so quickly that trying to display a splash screen would probably cause the program load time to take longer. We recently tested AutoCAD 2015 with and without the splash screen and startup time without the splash screen is cut roughly in half (from 19 seconds to 9 seconds). If you want to try this for yourself, follow the steps below.
Locate the icon you use to start AutoCAD (or a vertical such as Civil 3D). Right click on it and choose Properties.
In the “Target” field, go to the end, add a space, then add the text “/nologo” (without the quotes). Close the properties dialog.
The /nologo switch is only one of many startup switches available for use with AutoCAD.