Monitor won't recognize computer

Just got a computer on ebay. Supposed to work. Plugged it all in, turned it on, but monitor just says "no signal." Everything seems to power up ok, I've tried several different cables, the monitor was working just fine with the previous computer...the only thing odd that I've noticed is that the new computer doesn't beep when I turn it on. It seems to power up, the fan runs, I can hear 'computer sounds' inside -- just no beep.

10 answers Last reply
More about monitor recognize computer
  1. Hi profsteed, Welcome to THW.

    First off your PC may not beep unless there is a case speaker installed, some PC's built by individuals do not have them. If there is a speaker and no beep you have larger problems. :( But....

    Does your PC have a video card or is your monitor being plugged into the motherboard?

    Do you have any other monitor you can test with the PC?

    What type of cable are you using to connect the monitor?
  2. Thanks for responding, chief.

    It's an Acer PC -- not home-built -- so I assume there's a speaker. I have no idea whether the monitor is being plugged into a video card or the motherboard. I don't have another monitor to test with this PC, but the same monitor works fine with the PC I was using previously.

    The new PC has both VGA and HDMI jacks, as well as a third kind that I don't know the name of. I've tried all three connections, and in all three cases the monitor shows "no signal."

  3. Ok, if you have an Acer it should have a speaker and without a beep when you start your computer it means its running into some kind of error when starting up. But you will have to get the monitor working first. You should be able to tell if you are using a video card, the monitor connections will be horizontal rather than the vertical of the motherboard. And if there is only one output set, then your video is only off the motherboard.

    If your plugging into something like this:

    The 3 and 8 are your motherboard video out. Or a video card will be like this:

    Horizontal rather than vertical, it has a video card. If you are using a video card connections, Try to use the motherboard ones instead.

    Simple question, are you absolutely positive the monitor is setup for the correct input?

    If you have purchased this computer from a private seller on Ebay and not a Ebay store from a company like or, I would highly consider you contact the seller and inform him/her of the problem immediately and see what kind of options you can work out, for a return if I were you. If it comes down to it, do not pay to ship it back if the PC turns out to be faulty, have the seller provide you with a shipping label. If your get troubles from the seller your going to have to go through ebay or paypal buyer protection to get things straitened out.
  4. I've already been emailing the seller. He doesn't know what's wrong -- it all worked fine for him before he shipped it. If there's no relatively easy fix, I'm sure we'll work something out for a return/refund.

    As for the video jacks, there's a vertical VGA, as well as a horizontal HDMI and a horizontal jack that looks like #8 on your image (don't know what that one's called). I've tried all three.

    I don't know what the monitor is set up for -- but it does have a VGA and a #8 input. When I tried the HDMI, I did it on our TV (trying to use the TV as a monitor). The monitor works fine with a VGA connection, with the computer we were using previously. It says "no signal" when I try to use VGA or #8 from the new computer.
  5. Ok, well from the sounds of it you have a video card in the PC.

    So you have already tried every possible connection t the PC and the TV works on it over the HDMI? and it is still not working for you on the PC? Only thing I can think is there is a setting on the monitor or and auto detect not working correctly, or more likly the PC just for some reason is not putting out a video signal.

    The #8 port is a DVI connection. I would say to try to get the #8 DVI to work, because the video card should be your primary video device with that connection and it will go directly into your monitor as well with any converters/adapters.

    Have you tried to go into the monitor menu and select what input it should be trying to detect? Or if you have a manual for it look and see what the setup instructions say. If you do not have a manual for it maybe you can give me the model number and I can try to help you out more.

    Another thing you could try is if your Ok with opening your PC and taking out parts is remove the video card and try to use the video out from the motherboard, but don't try this if your not confident on doing so.

    Thats really all I can think of for help, its hard to diagnose these type of problems remotely. Let me know if you get any further with the few suggestions I did have to offer.
  6. Thanks for your help. I'll try your suggestions. What about the boot problem, though? Like I said, the computer doesn't beep when I start it up -- it doesn't seem to be starting from scratch; instead, it sounds more like it's coming out of sleep or hibernation. Could that be the problem? And if so, how do I fix it?

    I'll try the other stuff you suggested, in the meantime....
  7. Well I really have never encountered a problem like that myself so I am working blind here so to say. Without being there in person to see exactly what is happening, its hard to give suggestions on how to fix it.

    I suggested fixing your monitor first because without that there is no way of telling what is going on when you start your PC but obviously something is wrong with that as well.

    This is just me, but if I were you I would start to arrange a return unless you feel like spending a lot of time and maybe even more money on the PC to fix it. With it not putting a signal out to your monitor and not starting up there is quite a bit wrong with a supposedly "working when shipped" PC which if was packaged correctly would have been in the same condition as it left.

    You cannot trust what the seller tells you, he may be pulling your leg and knowing sold a bad PC, one thing is for sure is he was trying to make some $. I don't trust anyone on ebay unless they prove to me that I can, by good communication, and sending products that match to the T what they were described to be. If it was me I would have arranged a return as soon as I knew it didn't work. But like I said thats me and ultimately its up to you to make that choice.

    I really am out of advice or suggestions on what you can do, I am sorry I couldn't be of more help but without the PC in front of me its really difficult to trouble shoot it any further. Let me know how things go. If you somehow get the monitor to work then we can work on that boot problem. :)
  8. The monitor does work. It worked with our HP computer before I hooked it up to the Acer, and after the Acer wouldn't work I hooked it back up to the HP and it still worked with the HP. So I know the monitor works. Like I said, I'll try some of your other suggestions, and I'll let you know if I figure it out.

    And I did start arranging for a possible return. If I can't get it working in the next day or two, I'm sending it back....

    Thanks again for your help!!
  9. My suggestion would be to open the case and make sure everything is plugged in, if there are any parts unplugged, plug them in. Sometimes during shipping wires become undone, Espcially look for a graphics card in there and see if its power is plugged in, if it has an external power connector that is!
  10. @profsteed, I understand that your monitor works, but its not working with your PC, thats all I was saying.

    @computerrock1, I was assuming(I know I shouldn't but...) that even if the video card is not plugged in or correctly installed that the motherboard will be able to output the video to the monitor, but no video is coming from any output. As for the PC not booting correctly that may be caused by a unplugged component, but I also assumed that was checked before hand.
Ask a new question

Read More

Power Up Computer Monitors Components