How To Fix Monitor does not turn on when the computer starts

It’s great to have a powerful computer at home, on which games “fly”, open without brakes on 20 browser tabs, SSD pleases with the speed of work. However, if at one not very beautiful moment the display refuses to please with a picture, all the power of the system unit turns out to be useless.

Let’s consider why the monitor may not turn on , and what to do in such a situation.

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Why won’t the monitor turn on?

When the system unit or display does not turn on, expensive repairs are not needed. More often this happens for a trivial reason: there is no power supply or some minor breakdown. Maybe the electricity was turned off or the outlet broke.

However, the option with a power outage does not suit us, since we assume that the system unit is working, buzzing, the coolers are spinning, but the monitor does not show signs of life. In this case, the algorithm of actions begins with the fact that it is necessary to discard the most obvious reasons, and then proceed to the diagnosis. It is likely that you will have to look under the PC case cover .

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Monitor not working: what to do first

Modern displays delight with vitality. Many serve for 10 years or more without repair. Therefore, if the old monitor does not work, do not rush to panic. The absence of a picture on the screen does not mean that the display is broken. Perhaps the reason is in the computer or cable.

Power check

The most commonplace reason why the monitor does not turn on is accidentally pressing the power button of the device while it is idle. This can happen, for example, when dusting. After a while, the user turns on the computer and sees a black screen. The problem is eliminated in an elementary way – by pressing the power button of the display. This can be done at any time during the PC boot or after it has finished.

Checking the cables

If the cable is not equipped with additional fixing elements, it tends to fall off the connected device. In the case of a monitor, you must first ensure that the signal is supplied from the computer. If a VGA or DVI cable is used, it must be secured on both sides with screws. It is not desirable that the connection be broken when the technique is running. Otherwise, don’t be surprised at port problems. If the cord has come off, we fix it as expected.

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The monitor does not turn on when the computer starts: what else to check?

If it was not possible to solve the problem on a swoop, we proceed to a deeper analysis of the situation. You can start by locating the problem. If the monitor absolutely does not turn on when you turn on the computer, the reason may be:

The source of the problem Action options
1. Display Send to service or replace the defective part yourself
2. Cable Replace with a new one
3. Systemist Find the reason. Fix it yourself or send it to the service

Check the monitor, cable and system unit separately, for example, by connecting to a neighbor’s work equipment. The display can be checked by yourself. To do this, you need to turn everything off, disconnect it from the computer and connect it to the power supply. If a message appears on the screen that the cable is not connected, there is no signal, etc., this is a good sign. But the luminous LED of the monitor is not at all a guarantee of performance.

If the cord is faulty, take a breath: buying a new one will not be a problem. It is more difficult to deal with the display and the system unit. If the monitor breaks down, there may be a snag in the power supply. In this case, you may need to send the display to service.

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Power Supply

Here we will, of course, not talk about the power supply of the computer, but about the node that is responsible for powering the monitor. When the display does not turn on, the repairers are more likely to blame it and turn out to be right. Here you can draw a parallel with a sistemist who shows no signs of life. In both cases, the power supply regularly turns out to be the culprit, only in case of computer breakdowns is it a system unit, and in case of monitor failures – a board under the display lid or a separate block.

The monitor power supply unit consists of:

  • AC / DC adapter,
  • DC / AC inverter.

Both are voltage converters. The first block transforms the alternating voltage into direct voltage, and the second does the opposite.

Repair of the built-in power supply unit includes the following steps:

  • If there is a fuse on the board, check it first.
  • Visual inspection of capacitors. Soldering the swollen ones and replacing them with new ones.

It makes sense to take on the repair of the built-in power supply unit if you know how to read electrical circuits and work with a soldering iron. Otherwise, there is only one option – to carry the monitor to the service. A portable power supply unit is usually not repaired: in the event of a breakdown, it is replaced with a new one.

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Video card

If the monitor does not turn on when you start up your computer after installing or replacing a discrete graphics card , the high-power adapter may be running low on power. Vidyah developers write on their websites the minimum requirements for the power supply of computers. If, for example, 850 W is indicated there, and you have a 600 W power supply, the adapter, of course, is not required to start. Another reason for the problems is the incorrect installation of the vidyah: it was not properly inserted into the slot, it was not connected to the power supply, etc.

If you sin on the port of a discrete video card, you can try to connect it to the monitor with a different type of cable using an alternative connector. Burnt out HDMI? Try VGA connection. Or vice versa.

Now we turn to the diagnostics inside the system unit. Pull the power cable out of the case. Remove static from your hands by touching the radiator. Remove the discrete vidyahu from the case, connect the monitor to the built-in one. If it works, then you have found the source of the problem. Simply dumping the cable to a different port is not an option. It is imperative to remove the adapter from the housing. Only then will the computer understand that it needs to send a signal to the display through the motherboard port .

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The operative is the typical culprit for the lack of an image on the display. Especially if the computer has several memory sticks, the user added a new one, tried to overclock the old one, etc.

Did you stop displaying a picture after adding a bar? So the problem is in her or in the slot. Sometimes castling of dice helps. However, this option only works if they are in good working order.

If there are several straps, you need to try to start the computer, leaving only one of them – the one that was in the original configuration. It must be in the slot in which it was originally. If it doesn’t help, we continue to search for the source of trouble:

  1. We turn off everything without which the computer can boot: we remove the cables from the USB ports, we remove the network card, the sound system , the modem, the tuner, etc. from the case . In general, all the boards without which the system starts. Disconnect the hard drive.
  2. We turn on the computer. Did the picture appear? Fine. Turn off the PC and connect the disconnected devices one by one. If at some stage the signal ceased to flow to the monitor, the culprit is most likely the part that was connected last.

An alternative testing algorithm is also possible. You do not have to disconnect all the “superfluous” at once, but disconnect one part at a time, checking each time the signal transmission to the display.

If the motherboard has more than two memory slots, you must adhere to the layout of the strips. An unpleasant situation is possible when the user, trying to “start” the monitor, rearranges them incorrectly, although the reason was not in the RAM. As a result, instead of one problem, you have to solve two.

RAM or video card pins

There is one more factor that should be taken into account when looking for an answer to the question: what to do if a working monitor does not turn on. A signal on the screen may appear after cleaning the contacts of the RAM or video card. The contact surfaces of both components must be tidied up periodically. If your PC is old, it doesn’t hurt to pay attention to them at least once every six months.

A simple procedure allows you to get rid of the oxidized layer that prevents full contact between the board and the slot. It is logical to do this after cleaning the “engine compartment” from dust. There is no point in inserting clean contacts into a dusty slot. First we vacuum – then we rub the boards. Contact cleaning procedure:

  • we remove the memory chips and video adapter,
  • wipe the contacts on both sides with a rubber eraser,
  • insert back.

In the service, this procedure sometimes costs a tidy sum. If you hand over your computer to a dishonest master, he may say that he changed an expensive part, and will issue an impressive bill. Although, in fact, he just went through the contacts with an eraser.

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How else to assess the health of the monitor?

In addition to a computer, many have a laptop and / or tablet at home . The laptop usually connects to the display via the VGA interface without any problems. Most laptops have a familiar monitor interface. It’s even better when both the laptop and the display have an HDMI port. In this case, it is logical to use a more advanced interface. By the way, by HDMI, you can transfer not only the image, but also the sound.

The principle of connecting via VGA and HDMI is the same:

  1. We turn off the devices.
  2. We connect with a cable.
  3. We turn on the monitor first, then the laptop.
  4. If the picture did not go to the big screen, press Win + P. An alternative option is a function key with a display and a laptop. It usually needs to be pressed with the Fn button.

A picture appeared, is everything working properly? So the problem is not with the monitor.

Now an option with a tablet . You won’t find a VGA port on a compact device, and neither will HDMI. Manufacturers equip tablets with more compact connectors: microUSB, USB-C, etc. Therefore, you need an adapter to connect. This option does not require any additional gestures, in addition to connecting with a cable according to the above-described principle. We connect, check. If the display pleases with stable operation, we remove suspicions from it.

In conclusion, it is worth mentioning the BIOS reset option. If you adjusted something in it, after which the monitor stopped working, return the values ​​of the parameters that were there before. Can’t restore settings from memory? Reset BIOS to factory defaults. To do this, remove the battery and insert it back after 5 minutes.

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