How to Fix: Monitor Keeps Going Black / Turning Off

Infopackets Reader 'Tina' writes:

" Dear Dennis,

My monitor keeps going black. It flashes on and then off after a few seconds, then it goes to a black / blank screen. Sometimes I have to power it on and off 20 times before the monitor will work properly, and some days, my monitor won't turn on at all! When this happens, my monitor power light stays yellow as if the monitor is sleeping or in standby mode. Normally the power light is green when it is powered on and working properly. Any ideas why my monitor keeps turning off? "

My response:

There are many reasons why a monitor keeps turning off, resulting in a blank display. The best way to resolve this problem is through process of elimination; as such, I will go through the list of things you can do to help determine why the monitor keeps going black or turning off sporadically.

Here is a summary of some tests you can try to figure out what might be wrong:

• Ensure the Monitor Cables are Secure
• Review your DVI and HDMI Cable Configuration
• Ensure the Monitor Cables are Not Damaged
• Reset Power Management Options and Disable the Screen Saver
• Obtain the latest Video Card Driver
• Try the Monitor on Another Computer
• Repair or Replace the LCD monitor

I'll explain more further down.

Ensure the Monitor Cables are Secure

The first thing to do is to ensure that the monitor power cord and the monitor display cable are securely connected.

To get started, turn the monitor around to reveal its backside, taking note of the the cables running to it. The monitor power cord goes from the power outlet to the monitor. If it is not secure, the monitor simply won't turn on (indicating no power led in the front of the monitor), or it may cause the monitor to short out. In this case, ensure that the power cord is pushed in all the way and the connection is secure. Note that most monitor power cables have a C13/C14 connection.

Next, check the monitor display cable. The monitor display cable is the cable that delivers the picture from the computer to the LCD display. It runs from the back of the computer to the monitor, so you will need to check connections at both ends this time. To do so: go to the back of the monitor and locate the other big (usually black) cable -- it will be either a DSUB (VGA) 15 pin, DVI, or HDMI cable. Follow the cable all the way to the computer and note where it is plugged in. Now, ensure that the cable is screwed into both ends.

Note that HDMI cables cannot be screwed in. If you are particularly tight on space and/or if the cable is too thick to be bent properly (in order to make the connection), you might want to consider using an HDMI male to female adapter. I use these on my 55" LED TVs that use extremely thick HDMI cables. Otherwise, I wouldn't be able to plug the cable in.

Now, power the monitor on to see if it comes on. If not, try jostling the wires on the power and video cables to see if it causes the monitor to turn on or go blank. If one of the wires is at fault, then the display will turn on and off to coincide with your movement. If no change, proceed to the next step.

Review Your DVI and HDMI Cable Configuration

In the case of HDMI and DVI, there are some extra considerations to keep in mind.

Simply put: both DVI and HDMI are digital signals; if the signal is too weak, the monitor won't sync to the computer, resulting in a blank screen. If the cable run is too long, or of the signal has been split (using a non-powered DVI or HDMI splitter), this can cause the monitor to go black because the signal isn't strong enough.

Based on my experience, some HDMI cables will simply stop syncing properly after a while, even though they worked fine previously, and even though the same cable works fine on another device. Sometimes, HDMI cables won't work properly if there has been a recent hardware configuration change. For example, you may have purchased a stereo receiver and ran the cable through the receiver instead of directly through the monitor. In this case, you can bypass the splitter or receiver and see if that makes any difference.

At any rate, I suggest you try another HDMI cable (if you have one lying around) to see if that resolves your problem. If not, purchase one that has a high AWG (thickness) as this will help to ensure a strong signal. I suggest 6 feet (or larger) 24 AWG CL2 rated HDMI cables by Monoprice - I own many of them and they are excellent - and also available through Amazon!

Assuming that the cables are plugged in securely, power on the monitor and check to see if the monitor keeps going black. If not, proceed to the next step.

Ensure the Monitor Cables are Not Damaged

If a monitor power cord or display cable are pinched or twisted (especially at the very ends), this can cause the signal to become short circuited, and the screen to go blank.

In this case, you will need to unplug both the power and the display cable to the monitor (as well as the one to the computer) and physically examine them. Sometimes cables can be pinched if the computer desk is lying on top of them (usually because the desk has been moved or shifted). More often than not, however, the cable ends become bent or twisted usually due to a tight fit in the back of the computer or monitor, which results in the cable shorting out. Lastly, if you have a VGA or DVI cable, ensure there are no bent pins.

If you noticed any pinch marks or tears, or if the ends are badly twisted or bent, then you should try replacing the cable. If you have any bent pins, you can try straightening the pins using a screw driver - but ensure that the power to the monitor is unplugged beforehand.

If that doesn't resolve your problem, proceed to the next step.

Reset Power Management Options and Disable the Screen Saver

If you have Energy Saving Mode or a Screen Saver enabled on your computer, this can cause the monitor to go black or power off completely.

You can disable the Energy Saving Mode in Windows 7 and 8 by doing the following:

1. Click Start, then type in "power options" (no quotes), then click the Power Options link when it appears.
    
2. The "Select a power plan" page will appear; choose Balanced or High Performance from the list of power plans, then click the "Change plan settings" link on the far right of the window.
    
3. The "Edit plan settings" window will appear. Ensure that "Turn off the display" is set to "Never", then click Apply.

To disable your screensaver in Windows 7 and 8:

1. Click Start, type in "screensaver" (no quotes) in the search box; wait a few seconds and then click the Change Screensaver link when it is presented.
    
2. The "Change Screen Saver Settings" window will appear. Set the screensaver to "None" and click Apply.

Now, use the monitor to see if it powers off or goes blank. If it still doesn't work properly, proceed to the next step.

Obtain the latest Video Card Driver

The video card driver determines how the computer negotiates power saving mode with the monitor, among other things. To ensure that you video card driver is not at fault, download the latest video card driver from the manufacturer's website. You can determine which video card you have by opening up the Device Manager and reviewing the model name and number of the Display Adapter.

To do so: click Start and type in "device manager"; then click the Device Manager link when it appears. The Device Manager window should appear; look for "Display adapter" and click it. Your video card name and model number should be listed there. Most video cards are made by ATI (now AMD) or Nvidia; as such, you can go to either AMD's website or NVidia's website directly and download the drivers (rather than trying to search for one).

Use the monitor as you would normally after updating the driver to see if that fixes the problem. If it still doesn't work, proceed to the next step.

Try the Monitor on Another Computer

If you have tried all of the above steps, you have eliminated the majority of issues that can cause a monitor to go blank.

At this point you will want to determine if the computer or video card is causing issues with your monitor. To test this theory, reattach the monitor to another computer to see if it works properly. If it works on the second computer 100% of the time for a few days straight, then it is most likely the video card on the first computer that is causing you grief. In that case you will need to try another video card to see if that resolves the problem.

If that still doesn't resolve your problem, proceed to the next step.

Repair or Replace the LCD monitor

If you've made it this far in the process of elimination, then most likely the problem is with the monitor itself. In that case I suggest you try another (second) LCD monitor to see if that fixes your issue. If you have no issues with the second monitor then the first monitor is most likely bad. To verify that theory we once again use process of elimination. To do so, try the first monitor on another PC and see if you have issues on that system as well. If no issues then your first monitor is most likely somehow incompatible with your original (first) PC.

For example: a few years ago I had a monitor that kept turning off sporadically. Over time, the problem got worse, to the point where the monitor kept turning off and staying off with nothing but a black screen. Eventually I could not get a display from the monitor no matter what I tried, and it remained in standby / sleep mode with an orange light consistently. I verified this by using the monitor on another computer only to get the exact same result.

I managed to fix the LCD monitor by soldering new capacitors onto the power supply of the monitor (located inside the monitor). You can watch a video on Youtube on how to replace capacitors on an LCD monitor if you are technically inclined.

For most folks, however, taking apart a monitor and soldering on new capacitors simply won't be possible. As such, you can either take the monitor in for repairs, buy a used monitor (for relatively cheap), or purchase a new LCD / LED monitor. Keep in mind if you purchase an older, used monitor, you may encounter the same problem down the road.

If you do purchase a new monitor, I suggest spending a little extra and get one with a good brand name. Based on my experience, Samsung makes excellent monitors; they use premium parts (including premium capacitors), which should guarantee a long life ahead. I still have one Samsung LCD monitor from 2003 and it's still going strong.

I hope this helps you solve your problem.

RE: "Help me please! My monitor keeps shutting off!"

Although this article has been very comprehensive, I keep receiving emails from people "What do I do now / next?"

My suggestion is that you re-read the article from start to finish and try all the steps I just mentioned using process of elimination. Start with the cable: make sure it's tight and hooked in properly to both the PC and monitor. If it still doesn't work, then replace the cable using another brand and repeat. If that still doesn't work then try replacing the video card with another model / brand and test some more. If that still doesn't work then try another monitor. Eventually you'll figure out it's either the cable, video card, monitor, or possibly the computer that is the problem.

I kindly ask at this point please do not email me "What do I do next?" if you have a monitor problem, as I will simply refer you to this article. On the other hand if you have a separate computer question you'd like to ask me, then follow through to the next paragraph.

Got a Computer Question or Problem? Ask Dennis!

I need more computer questions. If you have a computer question -- or even a computer problem that needs fixing -- please email me with your question so that I can write more articles like this one. I can't promise I'll respond to all the messages I receive (depending on the volume), but I'll do my best.

About the author: Dennis Faas is the owner and operator of Infopackets.com. With over 30 years of computing experience, Dennis' areas of expertise are a broad range and include PC hardware, Microsoft Windows, Linux, network administration, and virtualization. Dennis holds a Bachelors degree in Computer Science (1999) and has authored 6 books on the topics of MS Windows and PC Security. If you like the advice you received on this page, please up-vote / Like this page and share it with friends. For technical support inquiries, Dennis can be reached via Live chat online this site using the Zopim Chat service (currently located at the bottom left of the screen); optionally, you can contact Dennis through the website contact form.