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I have been using electronic KVM switch for my two computers from one year. Today I was not able to connect one computer through switch. Error is no input signal. When I connect my monitor direct to that computer, it works fine. And even both computer lines connected to switch works fine with other computer. I can not figure out what could be the reason as switch works fine with its both connections with other computers. But, first computer show an error "no input signal detected" with both input connection of switch. The only changes I may have done in this computer is may be the resolutions. Does swith has any criteria which not works with certain resolutions or graphic settings ?

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In order to answer your question, you will need to provide details about the KVM switch; band & model. Please edit your question with those details so someone can help you. – CharlieRB Feb 12 '13 at 12:52
"first computer show an error 'no input signal detected'" -- How does this computer show an error? Do you mean this text appears on the (shared) monitor? "The only changes I may have done..." -- Either you made changes or you didn't; there's no middle ground. So what resolution changes did you make? KVM switches do have maximum resolution capabilities; check the specs for the device. – sawdust Feb 12 '13 at 21:20

You actually advised the most likely problem in your post where you said "The only changes I may have done in this computer is may be the resolutions.".

If the resolution of the computer is greater then the KVM/monitor can handle this is exactly the type of response you would see.

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Every KVM has a maximum resolution and refresh rate it can support. Many of them will display an error message on the monitor that will say something along the lines of

  • resolution not supported
  • refresh rate not supported

However, not every KVM will display this message, especially older ones.

Check your KVMs manual for acceptable ranges.

Many modern graphics cards can put out really high refresh rates for lower resolutions on VGA/analog connections, which might be the source of your problem.

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I would recommend checking the video port on the KVM Switch. The video port of the video cable you are using might be defective. Another option would be to check the supported resolutions on the KVM. If you changed anything in the settings of your system it might not work with the KVM Switch.

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maker and model of the KVM switch in this case ? It should be just "EDID feeding " issue. Not every KVM switches made equally. There are many makers did not build KVM switch support EDID emulation and feeding.

You want to use KVM switch support Full-time or All EDID/DCC feeding.

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