Member Avatar for debmae

Hello, my first post.

My desktop monitor is displaying "no signal input". My desktop computer sounds like its running but i have no image on the monitor except that message, plus the power light is showing orange instead of green.

I unplugged the monitor and connected it to my HP Laptop - and set the laptop up to use the second monitor from the personalization menu in the control panel.
My laptop detects that there is a monitor present, yet when I set it up to show my desktop on both the laptop and external monitor, click on apply and ok, the desktop monitor is still blank with the power light still orange.

The monitor was working fine last night and previous to that. I've had no problems with it and it's plugged into a UPS.

Does this mean my monitor is dead? or is there something else I can do? Suggestions appreciated. Thank you very much. debmae

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Short, practical troubleshooting notes for the "no signal input" case — expands on the good suggestions already in this thread. was right to mention laptop display hotkeys, flagged connector/pin issues, noted the video card as a possible cause, and ’s final discovery (a loose cable) is the most common real-world fix. The checklist below helps identify whether the problem is the monitor, the cable, or the PC before buying replacement hardware.

  1. Confirm the monitor’s own electronics: press the monitor’s Menu/OSD button. If the OSD shows, the monitor is powered and the backlight is OK; a “no signal” message then usually means a cable/input/source issue. If no OSD appears and the LED only shows standby, suspect the monitor’s power/backlight board.
  2. Check input selection and mode: cycle the monitor’s input (VGA/DVI/HDMI/DP). On laptops, the external-display function often needs the Fn+<display key> toggle (as @zorndyke noted); also try booting to BIOS or Safe Mode so the graphics driver/resolution isn’t hiding output.
  3. Swap cables and ports: replace the video cable with a known-good one and try other output ports on the PC (or an adapter). Inspect the connector ends for bent pins and tighten thumbscrews finger‑tight — avoid forcing bent pins.
  4. Cross-test components: connect the suspect monitor to a second PC/laptop, and connect the desktop to a different, known-good monitor or TV. If the desktop shows video on another display, the original monitor/cable was at fault; if not, the GPU or motherboard output is likely.
  5. Power-chain and hardware checks: try the monitor plugged directly into the wall (bypass UPS/surge strip). Reseat the GPU, try integrated video if available, and listen for POST/beep codes.
  6. If a very faint image is seen with a bright flashlight, that indicates backlight/inverter failure (repair vs replace decision).

Simple, low-cost checks (cable swap, input toggle, cross-testing) avoid unnecessary purchases — as this thread proves.

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Member Avatar for David Sanders

Sounds like a broken monitor sorry to say. The only other thing I could think is that the laptop external monitor port was also broken, but i doubt it. As for repairs, theses days its cheaper to buy a new monitor than to get it repaired. GL

Member Avatar for debmae

I sort of exptected to hear this. I'm going to try one more thing. I think I have another monitor cable around, I'm going to plug that into my monitor and try it on the desktop again as well as the laptop, Failing that, I suppose it's time to replace it. I appreciate your response. debmae

Member Avatar for zorndyke

did you tried to plug your monitor to laptop or desktop ?
if you connect it to your laptop, there is shortkey on your keyboard (Fn + F5) but depend of your laptop. If you still have problem with desktop PC, ist probably an error on data cable.

Member Avatar for Jupiter 2

It's not the monitor, per se, but the video card. As zorndyke says, try the monitor with the laptop first.

You also say that you can replace the video cable so I assume the monitor is one on those older types that has a cable that can be separated from the monitor? If so, check the pins in the connection on the end that has pins (ie cable and Monitor connection). Sometimes the pins can bend when a person plugs it in the wrong way, by mistake.

Is it an LCD Monitor?

Member Avatar for debmae

Thanks for your replies... I went out and bought a new monitor. When I went to unplug the old one that I had the problem with "no signal input" with, guess what! It was loose... I tightened it up and the monitor worked fine.... Lesson learned: First check your cables at boths ends before you go buy a new one.

Well, I did get a new 20" monitor for $100 from Staples. Not bad,, now what to do with the other one that is 19" and working just fine! Ha... silly me. Again, thanks for your replies.

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