After the computer shuts down the display light is also how to do?

Computer shutdown normal, not completely black screen display, is not the normal boot-liang, the switch is closed display case, it has closed its only power switch to completely black.I would like to ask how the case?

does not work, switch does not work if you switch out of the display of the power supply is provided by the host, it will not happen, but now a lot of In order to be able to host the power to host a stable supply of electricity is generally no longer the same as before the other to provide a display for the power jack, so the display can only directly take on other electric power supply socket, so that even if we Guan We should also have a host of the display switches it's also closed.