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Resolved Question

monitor says 'no signal detected' ...please help.

by Tylula / August 11, 2011 1:52 PM PDT

My son knocked over the tower on my PC and the monitor turned off. Now I can't turn it back on. It keeps saying 'no signal detected'

I have unplugged everything - plugged it all back in - even got a new monitor (an old one from a broken computer we had) and hooked that up - no good.
I tried a different cord.
I opened up the whole thing and cleaned it out. (although I suppose if anything was unhooked inside there I wouldn't know...)

Any other ideas?


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All Answers

Best Answer chosen by Tylula

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Test the monitor
by paul_saute / August 13, 2011 1:10 AM PDT

It is probabally not necesssary, but it is a good idea to check the monitor on a second computer. If it works on the other computer, then it is very likely the video card.

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by Tylula / September 14, 2011 9:58 AM PDT
In reply to: Test the monitor

Thanks everyone! I couldn't respond before because I never did figure out how o fix it - everything inside looked fine - so we just got a new one Wink

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by Willy / August 11, 2011 8:12 PM PDT

If the PC was running, then not good. Its more of a system problem than a monitor one. The "no signal" simply is getting nothing to display. In fact seeing that display is a good sign the monitor is working. Now, you need to check the PC more closely for any obvious damage. You can't take anything for granted. Open case again and observe operation, "what is it doing" and are there any more beeps than normal upon boot-up?

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monitor says "no signal detected
by 1great / August 12, 2011 12:33 PM PDT

I would suggest that because you have checked the cable between the monitor and the pc you have confirmed that the monitor is okay because you are getting the message that it is receiving no signal. I would unplug everything that you can including the power cord from any and all ends one at a time and plug them in again because I think your next move after checking for obvious damage is to take it to a technician. I am afraid it sounds like something is broken in the pc. May not be a big repair but may be it is. Hope it is just a broken wire. Good luck.

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Did you try...
by mwooge / August 12, 2011 12:51 PM PDT

Try unplugging the video board and plugging it back in.

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monitor became very light with lines running across it
by juanita nolan / August 23, 2011 2:58 AM PDT
In reply to: Did you try...

OS Windows Vista Home Premium Compaq computer and monitor
I took the monitor to Best Buy (where I bought it) the guy said it is cheaper to buy a new one. Any answers?

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Several Possible Issues Here
by Flatworm / August 12, 2011 9:28 PM PDT

The problem is could be damage to your video card; perhaps when the tower fell it damaged whichever receptacle on the back of your computer you have your monitor plugged into. Usually there are several, with most recent cards having at least a VGA and a DVI. If you just bought a new monitor you probably have the necessary cables to try using the OTHER one.

The impact of the fall may have caused the connection between your video card and your motherboard to come loose, or (and this is HIGHLY unlikely) caused the plug from the power supply to your video card to dislodge -- it would be the only wire running to the video card. Unplug everything, open your case, unplug the power connection to your video card, remove and reseat your video card and plug it back into the power supply.

If it still doesn't work you may need to replace the video card. If THAT doesn't work, try it in another slot (most motherboards have more than one PCI slot, which is probably what your video card uses).

If THAT doesn't work you may need a new motherboard, and it might be a simpler matter just to get a new PC.

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by pklri / September 18, 2012 1:11 AM PDT

You may also try reinstalling the firmware for the concerned monitor.

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Re: firmware
by Kees_B Forum moderator / September 18, 2012 1:25 AM PDT
In reply to: firmware

I've never seen a monitor that has the option to update it's firmware. Do you have an example of such a wonderful monitor?


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Not all that rare.
by R. Proffitt Forum moderator / September 18, 2012 2:08 AM PDT
In reply to: Re: firmware is one of many I've encountered over the years.

But the story repeats. That is, why folk don't go to the maker's web page for such things continues to be a mystery.
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