Shulou(Shulou.com)05/31 Report--

Hello, everyone. Lin Fei has come to answer the above questions. Why does the computer black screen only show the mouse arrow? many people do not know what happened to the computer black screen. Now let's take a look!

I believe that many friends have encountered the situation of computer black screen, such as 3354 computer boot black screen, monitor no signal, monitor black screen and so on. This paper makes a small summary of the causes and solutions of the common black screen in computers. I hope it will be helpful to everyone.

[computer boot black screen] the reason why the computer monitor is black how to turn on the computer?

1. Black screen failure caused by mainframe failure of computer

The black screen failure caused by computer failure can be divided into the following categories

1. Failure caused by mainframe power supply

Black screen failures caused by power damage or poor power quality of the host are common. For example, with the addition of some new equipment, the monitor has a black screen failure. After the quality and compatibility of accessories are eliminated, the poor quality of power supply and insufficient power are the main causes of the failure. At this point, you may hear 12 consecutive alarms from the internal horn. Replacing high-power and high-quality power supply is the best way to solve this kind of fault. In addition, some motherboards have AT/ATX dual power interfaces, which can also be caused by incorrect jumper settings.

two。 Faults caused by the quality of accessories

Poor quality or damage of computer accessories is the main cause of black screen failure of the display. For example, the motherboard (and motherboard BIOS), memory, graphics card and so on. It is certain that it may cause a black screen failure. The fault is orange, such as display lights. At this time, using the replacement method to replace the video card, memory, or even the motherboard, cpu, is the fastest solution.

3. Quality of connection between fittings

The main cause of the black screen failure is the improper or loose connection between the memory card and the motherboard, resulting in poor contact. And problems with the connection between the video card and the monitor can also cause this failure until the AT power is plugged in incorrectly. What's more, if your hard drive or optical drive data cable is connected upside down, it may also cause the boot black screen to fail.

4. Black screen failure caused by overclocking

Overclocking or overclocking parts that are not suitable for overclocking will not only cause black screen failure, but also cause damage to accessories in serious cases. There are overclocking or overclocking parts that are not suitable for overclocking, poor heat dissipation, or damage to the cooling fan in normal use, not rotating at all, and so on. Will cause the system self-protection collapse, black screen.

5. Black screen caused by other reasons

For example, incorrect CMOS settings on other motherboards and incorrect removal of BIOS jumpers on the motherboard will lead to black screen failure. At this point, you can change the settings according to the instructions on the motherboard. In addition, software conflicts, such as driver problems, improper installation, improper DIY, such as BIOS refresh errors, incorrect power management settings, hardware damage caused by malignant viruses such as CIH, etc. It may cause the monitor black screen failure. When you encounter this kind of failure, you might as well think more about the reasons for the failure, so that you can get twice the result with half the effort.

The second is the black screen fault caused by the failure of the display itself.

According to the author's usual experience, the black screen failure caused by the monitor itself is mainly caused by the following reasons:--

1. Insufficient AC power supply.

The lack of external power leads to the failure of some old monitors or power-consuming monitors to start normally, which is also one of the reasons for the black screen caused by the failure of the display itself. Or the external power supply voltage is unstable, too high or too low may cause the monitor not to work.

two。 Damage to power switch circuit

The fault of the switch circuit of the display is the main cause of the black screen failure of the display. Simple such as power switch damage or internal short circuit; common, such as switch tube damage or damage to its peripheral circuit components, and so on.

3. The line output circuit is damaged.

The fault of the output circuit or picture tube and its power supply circuit is also the main cause of the black screen failure of the display. Especially for some miscellaneous brand displays which have been used for many years or of poor quality, it is more common that the black screen is not displayed due to the damage of high voltage package.

Third, the troubleshooting ideas of computer black screen.

How to fix the black screen failure of the display, we will put forward some ideas for your reference.

First of all, we can solve this problem

When you have a black screen failure when assembling a computer or replacing parts, you should first check the installation quality of your accessories. For example, whether the memory bar is installed correctly, whether it is in good contact with the motherboard slot, whether the graphics card and other plug-in cards are installed in place, and whether the relevant settings in the selection of BIOS and jumper on the motherboard are correct, you can carefully refer to the relevant card instructions for setting. In addition, it is also necessary to focus on checking the quality of the card itself, as well as whether the relevant slots on the motherboard and the "Goldfinger" part of the card have foreign bodies and are contaminated by dirt.

In addition, whether the CPU is overclocking or mistakenly overclocking (especially some motherboards with soft jumpers, the system's "automatic" error setting is more likely to cause this kind of failure), whether the data cable of the hard disk or optical drive is connected upside down, and so on, all need to be considered. And for this kind of problems, it is best to give priority to the "minimum system method" and "replacement method" for diagnosis, leaving only the motherboard, graphics card, memory and CPU of the host to try, especially the failure rate caused by the quality of memory strips is relatively high. If there is no problem, you can focus on checking the quality of other accessories. If the screen is still black, you can carefully install and connect these accessories, and then restart. If the problem cannot be solved, you can use the relevant components.

In addition, it is important to know whether the mainframe power supply and power switch are good or bad, and whether they are connected properly. It is possible to cause the whole machine to go black, and you need to focus on these. If there is a problem with the power supply, then you can see that the lights on the chassis panel of the mainframe are not lit after the computer is powered on, and you can not hear the sound of the power supply fan turning and the sound of the hard disk self-test in the host computer, and so on. This means that your host system is not powered properly at all. For this kind of problem, you should first check if there is an AC power supply outside and use a measuring pen to see if there is power in the power outlet. Next, you can test whether there is electricity on the side where the power cord is connected to the mainframe power supply, and if necessary, use a multimeter to test whether the voltage is sufficient. If the voltage is too high or too low, it may cause the mainframe power supply to overvoltage or the undervoltage circuit to stop automatically.

two。 Listen to sound, view color and distinguish faults

When there is a black screen fault in the computer, more often than not, the indicator light of the mainframe panel is on, and the fan in the machine rotates normally, but the alarm sound of the PC horn appears; or the related equipment in the chassis, such as the hard disk, normally self-tests, but the monitor does not show. At this time, in addition to overhauling according to the above method, it is more important to learn to distinguish the error reporting law of the PC horn to identify the fault. in addition, it is also very useful to observe the light and off of various indicators of the host or display when the fault occurs.

For example, the host self-test normally, but the monitor has a "black screen" fault. For this fault, we can focus on the idea of motherboard-display card-monitor cable-monitor. First of all, you can check whether the display power indicator is lit, if normal, you can focus on adjusting the brightness, contrast button, eliminate "common" this kind of false black screen fault. If there is no problem, you can focus on checking whether there is something wrong with the connection cable from the mainframe display card to the monitor, whether the pointer in the plug on the cable is askew broken and whether it is closely connected to the display card. In addition, you can also remove this cable connector to see if the monitor can illuminate properly or connect the monitor to another host. In order to determine whether the fault is caused by the host or the display itself.

For example, the display screen is black and the horn in the host machine emits a long, two or three short beep or continuous beep, indicating that there is a problem with the connection between the display card and the motherboard or between the display card and the display. you can focus on checking whether there is a good slot contact and whether there is a foreign body in the slot and can replace the graphics card to try, if there is no improvement, you can initially show that the problem is on the motherboard, you can take the graphics card to another motherboard to try. For example, if there are continuous long tweets, most of them indicate that there is something wrong with the memory bar, and you can focus on checking the installation contact between the memory and the memory slot. If there is a continuous short sound of ticking in the machine, it indicates that there is a slight short circuit in the machine, and the problem can be solved by minimum system method and elimination method until the short circuit position is found. In addition, if you hear two short beeps, it indicates that there may be a problem with the motherboard or display card or monitor. If you do not connect the monitor, if you still call like this, there is a problem with the display card. If it becomes a short tone, it indicates that there is something wrong with the display end.

For the black screen failure caused by the display itself, we mainly provide you with more specific maintenance ideas from the following points.

1. Rapid maintenance of black screen of display

If there is no display after the display is turned on, after excluding the cause of the host, you can first check whether the display protection circuit is working because the voltage is too high or too low, and check whether the acceleration pole voltage is normal. In addition, the key point is to check the following parts that are prone to problems, such as whether the fuse has been fused, whether the rectifier bridge switch tube has been broken, whether the current-limiting protection resistor has been burned out, and so on. These parts can sometimes be seen from the appearance of blackening and other fault phenomena. Then focus on checking the line output tube, transformer, low-frequency rectifier tube, high-frequency rectifier tube and other key parts of the damage or performance decline or virtual welding and so on, the general display black screen fault you can quickly get rid of the disease.

two。 Fault diagnosis of Line scan Circuit

The failure of the line scanning circuit is an important reason for the non-raster and screen display after the display is powered on. For this kind of fault, the focus of maintenance can be placed on the line scan circuit, and the line oscillation circuit can be checked first to see if there is a problem. Under amateur conditions, in addition to checking whether the peripheral components of the line oscillation chip are damaged, the line oscillation chip can also be replaced first. In addition, the line drive tube is damaged or its working condition is abnormal, the line output tube damage or line output load problems may cause the above faults. At this time, you can overhaul and replace these parts. If there is something wrong with the line output circuit, it will generally return to normal after this overhaul.

3. Fault diagnosis of Picture Tube and its Power supply Circuit

The abnormal picture tube and its power supply circuit can also cause the fault of non-raster black screen powered on the display. At this time, we can first check whether the picture tube filament is bright, and use a meter to measure the filament power supply circuit to see whether the filament voltage is normal. In addition, if it is found that the filament electric blocking needs to replace the good filament current limiting resistance, if it is found that the picture tube filament is broken, it is necessary to replace the picture tube. If the above is normal, we can focus on checking whether the accelerating pole voltage of the picture tube is normal, especially the breakage of the accelerating pole voltage is the main cause of this kind of failure, which can be replaced. If there is a high voltage, we can focus on replacing the line output transformer (high voltage package) to try, the damage of this part is one of the main causes of the black screen failure of the display. In addition, while overhauling the above, we can also check whether the lower cathode voltage and apparent discharge voltage are normal. If the apparent discharge voltage is not added or its voltage is not normal at all, it is also one of the important reasons why the display is powered on without raster and black screen.

At the end of this article, I hope it will be helpful to you.

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