Are they actualy connected to any signal source?
If there is no signal, a brief "No signal" message is displayed, then, the screen goes into sleep mode and goes blank.
Check all cablings. The cables need to be connected to the monitor and a signal source.
A cable between the two monitors won't do, a monitor is not a signal source and probably can't be used as a relay.
Electro
July 2013
Automatic Answer
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