Computers and HDTV video source devices can sometimes lose the EDID -- basically the electronic identification of a display which lists its possible resolutions and frequencies. When displays are switched away or disconnected and then reconnected the EDID can be lost and the computer or HD video source device can lose the ability to display the image properly. The Gefen DVI Detective Plus allows you to switch or relocate HDTV or Computer video displays while "tricking" the source devices into thinking that the display is still present -- maintaining smooth video operations throughout the process.