...you leave both cables attached?
I have a T24D391 HDTV as a monitor in extended desktop with another one.
Computer and monitor are connected with a HDMI cable. When i turn off the computer, the monitor doesn't go in sleeping mode: it is still searching for the signal.
I tried with the VGA cable and it works: when the PC shuts down, the monitor goes in standby mode. But for obvious reasons I'd prefer to use HDMI instead of VGA. Furthermore, when they are connected with VGA, the monitor makes a strange noise, like the coil whine.
How can I make my monitor go in standby mode when I turn off the computer?

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