Posted 16 January 2009 - 07:49 PM
Having a second monitor work correctly on your system indicates the problem lies with your Acer. Check that the video out on the computer hasn't defaulted to a refresh rate the Acer can't handle, but the spare monitor can - the Acer's "out of range" indication may be the flashing signal.
Beyond that, as rigacci suggests, try the Acer on another computer, or even power it up not connected to anything. Most monitors under this condition will display a splash screen then indicate "No Signal" or similar before going into standby.
If it won't operate correctly in either of these circumstances, I suspect it probably has some bad capacitors in its power supply. This can cause the situation you've described. As long as the monitor stays connected to the mains and just goes between standby and power-on, it works, but once the mains power is removed, the PSU can't kick into gear again because of weak capacitors.
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