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When I come back to my computer, after leaving it on overnight, the display gives me a no signal message. I cannot get the Windows login screen up on the display, via the DVI cable alone, no matter what I try.

So I connect the computer to the display using a VGA cable (beside the DVI cable) and that gets me the Windows login screen. Then I unplug the VGA cable and I still have the Windows login screen (!?) but now it's obviously coming through the DVI cable.

Does anyone know why this might be? I'm running Windows XP SP3, the desktop is an Acer S680G and the display is an Acer B223 WL. I'm using power scheme 'Always On' as this box has to run processes around the clock.

Any help to avoid this dance of plugging and unplugging would be appreciated.

share|improve this question
"no matter what I try." - What did that include? – Ƭᴇcʜιᴇ007 Feb 12 '12 at 23:49
good question :) - basically trying as many keyboard and/or mouse input combinations as I could think of e.g. Ctrl-Esc, Alt-Tab, function key combinations etc. - there might well be some special combination that I don't know but I suspect it might be the way the computer and display are configured, considered together, that makes it not possible to bring up the display by keyboard and/or mouse input alone... – Sean Feb 13 '12 at 0:49
Last night I had an RDP session open to each of my two work machines. When I switched on the work monitor I use for both machines this morning the monitor would not display video from either machine no matter whether I used VGA or DVI. Had to reset the workstation machine. So perhaps there was no video output to the work monitor from either machine because each was sending the video output to the still-open remote sessions - Is that possible? – Sean Mar 1 '12 at 22:53

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