Computer turns on but monitor is not working

What to do if monitor doesn’t turn on

Often the cause of the problem is not the display itself, but the computer. Check each option and solve the problem yourself.

Before proceeding with further diagnostic testing, you must make sure that the monitor is receiving power. This is indicated by the LED on the front panel, which should be illuminated or flashing one of the colors.

If the light does not turn on, check the power buttons on the monitor and extension cord: maybe someone or yourself accidentally pressed them while cleaning and didn’t notice them.

computer, turns, monitor, working

If everything is fine there, the cause may be in the cable. On the plug side, it fits snugly and securely into the socket, but the monitor’s power connector just snaps into place. The wire might be slightly displaced in the socket and the contact is broken.

Try plugging it in a bit more and check the LEDs. The problems can also be with the cable itself. To rule them out, replace the wire with another one, such as from a computer power supply. they fit (unless it’s a model with an external adapter).

Why the monitor turns on and off

In some of these typical cases the cause is in the power supply. But it is not always a direct failure. The thing is that many modern LCD monitors use automatic diagnostics for detecting defective nodes and in case they are present they behave accordingly. For example, if the inverter, that supplies power to monitor backlight, detects even one burned out fluorescent lamp, it will stop its operation and send the error signal to the control unit. So if the monitor turns on and then immediately goes off, the problem with the power supply is not always the root cause. It is possible that in this way the device has simply secured itself from a further, more serious malfunction.

Other faults also include blown capacitors in the power supply, electrical current breakdown in the inverter transformer winding, static charge build-up as a result of strong electromagnetic interference (e.g. after a thunderstorm), etc. In the table the most characteristic signs of typical breakages and their possible reasons are listed.

Cleaning the system from dust

As you know a lot of dust and dirt is regularly deposited and accumulates inside the computer hardware. If the computer is working, but the monitor does not turn on from the first time, it is possible that it is time to clean the “guts” of your “iron friend.

  • Firstly you need to switch off PC from power supply and disconnect connection cables. This way you eliminate the risk of electrocution and eliminate the static voltage inside the case;
  • After shutting down completely, take a screwdriver and open the side cover of the system unit;
  • Remove the dust from the internal components;
  • When you’ve collected all the debris, remove the graphics card;
  • Gently clean the contacts with a pencil eraser and remove dust with a brush.

We recommend cleaning not only the graphics adapter, but also other components, including: coolers, RAM, hard drive, chipset, and even empty slots.

Check fan noise, beeps, and power indicators

To determine if the problem is related to the computer or monitor, turn on the computer, listen to the sounds, and look at the indicators.

If the computer beeps when starting up, the board, cable, memory module, or processor inside the computer may be loose. Proceed to Reinstall internal components to check for loose components.

If you don’t hear noise of fans and lights on your computer don’t light up then the problem is in your computer and not in your monitor. For troubleshooting a computer that won’t start, see Computer won’t start.

If you hear a fan noise and the computer indicators light up, the problem is probably related to the video cable connection or the monitor. Proceed to the next step.

The computer turns on, but does not start

Probably the most popular query on the web that relates to a PC startup problem is “Computer turns on but won’t start”. As you’ve probably already guessed, there can be a myriad of reasons for this problem But let’s briefly go over the main causes and ways to fix them.

So, for example, if you hear a characteristic noise from the computer case, but there is no image on the screen, then carefully examine the connection of your monitor to the video card PC. We strongly advise you to check the quality of connection of not only the video cable, but also the power cable.

Also listen carefully to the sounds your PC is making. You may see some information on the screen. But the calculation of the malfunction exactly by the post-signals (peeps) is the most correct decision on the way of identifying and eliminating the problem. True, you need to find the deciphering of these signals in the official instruction manual for the motherboard, or use the services of search engines.

These two problems were related to the “iron part” of the computer. But very often the reason why the computer turns on, but does not start is a problem with the operating system. If after turning on your computer, BIOS has successfully passed all the checks, but the system still does not want to start, then you need to proceed to the solution of this “software problem.

computer, turns, monitor, working

Here you have several ways to go. The first of these is to reinstall the system. Of course, this approach is very radical and fraught with loss of data and programs. Nevertheless, you will get a clean and working system, which is pretty good. The second is to boot from a live image. That way you can pull out all the files you need from being deleted. And after that proceed to reinstall the system completely. In a number of cases this is almost an ideal solution. The last, safest (but not always the most effective) way is to try to recover your system using a bootable disk. Here you can either recover your system by rolling back to the last stable restore point (if you have one set up), or the wizard will try to recover the system by itself.

Problems with connection of the monitor to the computer


If when you turn on your computer you get a message that there is no signal on the monitor, then the first thing you should check is the cable you use to connect the monitor to your computer. There are usually two problems with a cable: it might loose connection to a computer or monitor, or the cable might be faulty and need to be replaced.

The first thing to do is to check the contact at the cable connection points. To do this disconnect the cable from the monitor and the computer and reconnect it. If it’s a DVI or VGA cable, be sure to tighten the two screws which fix the cable in the connector.

Breakage of a cable that has worked fine before is a rare occurrence. But if you have another cable at hand, or if you can remove one from another computer, you can check how the monitor will work with another cable. Perhaps after replacing the cable the problem will be solved.


Another possible cause of problems are adapters. If you connected your monitor with an adapter and you get a “No Signal” error, it’s most likely because of the adapter. Such adaptor could be connected incorrectly or it could be unsuitable for your current equipment.

For example, DisplayPort to HDMI (DP) adapters only work one way, which means that they can convert the signal from DisplayPort to HDMI, but not vice versa. At the same time, if your video card has several DisplayPort video outputs, the DisplayPort-HDMI adapter will only work on the first one.

Passive HDMI to VGA adapters can only work on devices that support HDMI analog output. This feature is available on DVD players, most likely video cards with this feature do not exist.

A passive HDMI to VGA adapter, will only work on some DVD players.

Active HDMI to VGA adapters (with a box) convert the digital signal to analog, so they can work with any video card. But the conversion is made only in one way, or from HDMI to VGA or vice versa, depending on the model.

If possible, try to connect the monitor without using any adapters, it may solve the problem with the lack of signal.

  • Some older graphics cards require drivers to be loaded in order for the DisplayPort video outputs to work. In such cases the main monitor has to be connected in a different way otherwise you won’t get a picture in BIOS or when booting from a USB stick.
  • Not all USB-C ports on notebooks can be used for connecting monitors. Some laptops do not support video output via USB-C at all, and some laptops only have one port. Also it is highly recommended to use original USB-C cable that came with the monitor for USB-C connection since not all cables support video.
  • Integrated graphics can be disabled in the BIOS. So if you change from discrete to integrated graphics, you must enter the BIOS and check the settings.

The monitor does not work due to its own malfunction when the computer is turned on

The monitor itself may stop working due to some reasons beyond our control. It can be either a power surge, material fatigue, or just a failure of some electronic component. This could explain why the monitor does not work when you turn on the computer. At home to fix a broken monitor is unlikely to succeed. Of course, if you are an employee of a service center with experience you will be able to cope with the repair of the monitor with your own hands. But most people are simple users. So it only remains to properly diagnose the problem and send the device to the service center.

Logically, a screen malfunction can be considered a condition where it is “silent” at all. That is, the indicators are not lit and there is no image, as well as the monitor does not turn on from the first or subsequent times. To determine if the monitor itself is to blame for this problem you can, in fact, do two things: check the power and video cables. The whole amount of checking comes down to finding a similar wire and testing it on our suspect. If you are familiar with other ways to diagnose and troubleshoot monitors, you can share them in the Комментарии и мнения владельцев.

Method 5. Hardware Check

The last step is to look at the actual hardware. Before you do anything else, try disconnecting all devices from your computer, such as your keyboard, mouse, external hard drive, speakers, printers, scanners and the rest.

Sometimes a problem with other hardware can cause your monitor to go out, but your computer to work. If that doesn’t solve your problem, you need to check the port connectors on your computer and on your monitor for damage.

Many users don’t remove the cable correctly, which can cause it to break over time. Sometimes people try to insert a cable into a connection that was not designed for it, which causes damage to the ports.

If this happens you don’t have many choices. you need to take your computer to a service center to fix bent or damaged ports.

If you’re a little tech savvy, you can try opening up your computer and checking that the hardware, particularly the motherboard or hard drive, is connected correctly.

That’s it! We hope that you have managed to solve the problem yourself, when the monitor does not show the image, but the computer works. Otherwise you should take your computer and monitor to a service center.

computer, turns, monitor, working