To change the Displays icon in System Preferences to display your actual computer, navigate into: Open another Finder window, and navigate into this folder: Replace (after backing it up, of course) the Displays.icns file in the first window with an icon from the second window -- preferably one matching your computer from the com.apple. series. You might need to empty your system caches before it starts showing up. This is a system hack, so as always, please back up before doing anything dangerous.