I have a Mid 2011 2.3Ghz Mac Mini w/HD3000, running 10.7.5. It is a server, and does not have a display or HDMI cable attached to it, yet when I connect to it via Apple's Screen Sharing program or some other VNC app (JollysFastVNC) I still get black areas. Any area of the screen that is changing (clock, iStat Menus, etc.) are always visible, or when I toggle between applications I get new displayed areas. See attached screenshot. A restart does not always fix this, any ideas?