At present, there are two main reasons for computer black screen, one is hardware failure, and the other is software conflict. The difference between them mainly lies in the location where the black screen occurs, that is, when it is turned on or when it is used normally.
Of course, neither hardware failure nor software problem is isolated in a sense. Try to solve it according to the following ideas. I believe that the black screen will be properly solved soon. Black Screen Hard Injury When a "black screen" suddenly appears after the computer is turned on, please pay attention to whether the PC speaker in the computer has an alarm sound.
If the PC horn sounds an alarm, then we can initially determine the hardware components that may have problems according to the length of the sound. For example, when the computer is turned on, the alarm sound of the PC speaker is one long and four short. According to this prompt, it is easy to judge that the problem lies in the graphics card.
If so, readers can open the case and see if their graphics card is firmly inserted. If it feels a little loose, please re-insert and tighten the video card, and then fix it with screws.
If the problem of insertion mode is eliminated and the card slot is relatively firm, you can try changing the graphics card to another slot on the motherboard. If the user's graphics card does not belong to PCI but is a new AGP slot board, and there is only one AGP slot on the computer motherboard, you can try another AGP slot on the motherboard to eliminate the physical failure of the graphics card.
If the graphics card is inserted tightly and the physical fault is eliminated, then there is another possibility that the "golden finger" of the graphics card itself has a problem in normal contact. If this is the case, you can pull out the display card again, and then find a clean rubber to rub it back and forth on the "golden finger", because most of the poor contact problems of this "golden finger" are caused by some dirty things on it.
If the alarm sound of the PC speaker is not long but short when the computer is turned on, but a short and urgent call, and there is a black screen, then it can be roughly judged that there is a contact problem in your computer memory according to the phenomenon. The solution to poor contact is basically the same as the display card, that is, insert * * * and then insert it. Be sure to insert it to the end when inserting it, and fasten the clips on both sides of the memory module.
SDRAM slots on some motherboards are troublesome, because most of the slots on these motherboards are very tight. If the user encounters this situation, he must not use force. They can press the bottom of SDRAM slot on the motherboard with their fingers, and then press the memory with their thumbs. Hearing a slight noise proves that the memory has bottomed out. Finally, they can fix their memories with clips. There are also some black screens, and the computer will not call the police. At this time, the simplest thing is to analyze the specific problems according to the mathematical "exclusion method".
First, check whether there is any problem with the power terminal board, remove the relevant supporting parts of the computer and replace them with some other equipment that can be used to check whether the power terminal board works normally. If there is nothing wrong with the power terminal board, then check whether the connection between the computer power supply and the motherboard is normal according to the normal procedure, that is to say, check whether the motherboard power supply is normal.
If the socket is not connected by mistake, check whether the power supply is burnt out. If the power supply burns out, the power supply fan will also stop running. In some early computer cases, the power supply was often insufficient. If this problem is suspected, please unplug all power cords from the hard disk, CD-ROM drive and floppy drive, and then restart the computer. After the power consumption rate is greatly reduced, see if this situation is solved.
If the problem still cannot be solved, please rule out that the motherboard BIOS is accidentally damaged by viruses such as CIH, and whether the motherboard is in poor contact or the welding head is short-circuited. In addition to the above, with the continuous improvement of CPU frequency speed, power supply plays an increasingly important role in the whole PC power supply system.
Some people describe the central processing unit as the heart of a computer. Maybe for a long time, we were too concerned about whether the heart is healthy and strong, but neglected the chassis power supply that can provide power and energy for the heart. However, due to the lack of power supply, it may also cause the computer to have a black screen.
The symptom is that you can hear the chassis power fan start normally after starting, but you can't hear the "drip" sound of system error, but the machine doesn't work, there is no self-test process, and a black screen is displayed. If all boards and memories are plugged and unplugged again after cutting off the power supply, make sure that all boards or components are not loose, which is mostly caused by insufficient power supply.
I strongly believe that for your love of computer health, don't ignore the chassis and power supply when buying a computer. Buying a power supply with a rated power of more than 250 watts is a kind of care for your machine. There is one more thing to note here. At present, many power supplies with rated power of 250W on the market simply can't meet the requirements, which leads to another suggestion. Buy power supply and try to take care of famous brands. At this time, the brand is a powerful guarantee for the safety of your machine.
If there are many peripherals installed on your machine, such as dual disks, dual CPUs, dual optical drives, SCSI cards or anything else, you'd better find a more powerful (300~400 watts) or server power supply. As for users of P4, Thunderbird and GeForce3, they must use more than 300 watts of power, otherwise things more troublesome than black screens will emerge one after another.
Of course, the phenomenon of black screen is mostly caused by hard injuries on the PC, but it is not absolutely so. Soft injuries may sometimes be easier to deceive users. In the process of using our computer, some black screen phenomena may also be soft failures after entering WINDOWS 98/WINME/WIN2000 or even WINXP system (but I haven't found the black screen failure of WINDOWS XP yet, but since there is no conclusion, it can be assumed that it also exists).
If users find that the machine is assembled, there are always inexplicable problems in the process of installing operating system and other software, or even a sudden black screen crash. Here, it is necessary for us to eliminate the cause of the virus, because there are many cases in which the virus causes the black screen in the system operation, but the only solution is antivirus, and there is nothing to say.
On the contrary, we should pay more attention to errors or black screens in program operation. Here you are.
2. Why does the computer screen always fail to receive the signal and automatically go black?
I suggest you check the signal line behind the monitor and the host first. Most of them are virtual connections, which is the reason. Second. Dust pollution to the graphics card will also cause this phenomenon.
Details are as follows:
The failure of black screen of display is common, which often shows that there is no image on the display after booting, but the "beep" sound has been heard when the host computer starts normally; Or in use, the display screen suddenly turns black; There are also some computers that start normally, but when they start to a certain step, a black screen appears. It is precisely because once the display screen is black, you can't see any prompt information, and you can't handle it accordingly to solve the problem, which is generally a headache.
Cause analysis and elimination of failure:
I. Show
Black screen caused by monitor's failure to work normally due to its own reasons, such as poor contact of monitor power cord and power plug (note: both ends may be possible), power switch disconnection, and internal circuit failure of the monitor.
Two. Signal line
The display used in PC adopts the connection mode of 15-pin D-plug, in which 13 and 14-pin are synchronous signals of line and field. The display determines whether to open the filament and the high-voltage power supply path by judging whether these two signals exist, and at the same time, combining the positive and negative polarities of the signals and different line frequencies, these two signals are used as transmission signals in the display mode. If the line and field signals are lost, the power indicator of the display is green, but no image is displayed; If all are missing, the power indicator of the monitor is orange and no image is displayed. In this case, it is mainly to check whether the D-type plug of the display signal line has broken feet, crooked feet or short feet, and whether there is any disconnection inside the signal line. The solution is to replace high-quality signal lines.
We have a "video off method" in the power management of CMOS settings of computers, including three options: "V/H SYNC+BLANK, black screen, DPMS". The first option is to select the display card to output line field signals to control the energy-saving mode of the display.
Three. Graphic card
The most directly related to the display is the graphics card. If there is no signal from the graphics card or there is a signal that cannot be sent out, the display screen will definitely not light up. In actual use, the display card is not compatible with the motherboard, the signal output socket of the display card is in poor contact or loose, which leads to the damage of the display card, and the poor contact between the display card and the AGP slot of the motherboard will lead to the display not being bright. Troubleshooting this kind of fault requires careful patience, carefully check the contact between the graphics card and the motherboard, and see if there is any unstable contact. Incompatibility can only be judged by experience and data.
Four. Power?Supply?
Everyone always spends more money on CPU and memory when configuring the machine, but always locks the door on the power supply. However, as the power supply of all computer components, if something goes wrong, can other components still work normally? As we all know, if there is a power failure, the host will give a continuous short beep alarm and the display screen will not light up. However, there are times when you say nothing. Finally, it was found that it was the power supply.
Verb (abbreviation for verb) mother board
The main reason is that CMOS settings are wrong. The first initialized graphics card is set to PCI or onboard AGP graphics card, but the monitor is not connected in the corresponding position. Results The computer started normally, but the display screen was not bright.
Furthermore, the conflict between CPU, memory or graphics card, sound card, modem and network card will also lead to the failure of the host computer to start, which will lead to the black screen of the display.
Software conflict of intransitive verbs
Due to the universality of PC and its strong vitality, thousands of software companies have been established in Qian Qian, and countless applications have been written for everyone. However, because these different applications are written by different companies, when they are put together, they may cause a black screen due to address call conflicts. The most typical feature of this fault is that after installing a certain software, the system prompts to restart, and after self-checking the screen and the blue sky and white clouds of WIN98, only the cursor flashes on the display screen, and then there is nothing. The solution to this kind of problem is also very simple. Just remember what software you just installed, hold down the "Ctrl" key when starting, select item 3 to enter the safe mode, and then uninstall the software you just installed.
Seven. Viral damage
Viruses are extremely destructive, especially with the advent of the Internet era, more and more viruses spread through the Internet. Viruses, such as CIH, which can lead to the black screen of the display, are extremely destructive, and directly rewrite the BIOS chip of the motherboard, resulting in the machine being unable to start and self-check. If there is no programmer, your motherboard can only be scrapped. Sometimes it may be because the BIOS chip is damaged by the virus, which leads to the misjudgment of the maintenance personnel and delays a lot of time.
If the virus maker understands the working principle of the graphics card and controls the output of the graphics card through the program, it will also cause the display to be black, but generally it can only be black after entering the system.
3. The computer screen can't receive the signal black screen.
At present, there are two main reasons for computer black screen, one is hardware failure, and the other is software conflict. The difference between them mainly lies in the location where the black screen occurs, that is, when it is turned on or when it is used normally.
Of course, neither hardware failure nor software problem is isolated in a sense. Try to solve it according to the following ideas. I believe that the black screen will be properly solved soon. Black Screen Hard Injury When a "black screen" suddenly appears after the computer is turned on, please pay attention to whether the PC speaker in the computer has an alarm sound.
If the PC horn sounds an alarm, then we can initially determine the hardware components that may have problems according to the length of the sound. For example, when the computer is turned on, the alarm sound of the PC speaker is one long and four short. According to this prompt, it is easy to judge that the problem lies in the graphics card.
If so, readers can open the case and see if their graphics card is firmly inserted. If it feels a little loose, please re-insert and tighten the video card, and then fix it with screws.
If the problem of insertion mode is eliminated and the card slot is relatively firm, you can try changing the graphics card to another slot on the motherboard. If the user's graphics card does not belong to PCI but is a new AGP slot board, and there is only one AGP slot on the computer motherboard, you can try another AGP slot on the motherboard to eliminate the physical failure of the graphics card.
If the graphics card is inserted tightly and the physical fault is eliminated, then there is another possibility that the "golden finger" of the graphics card itself has a problem in normal contact. If this is the case, you can pull out the display card again, and then find a clean rubber to rub it back and forth on the "golden finger", because most of the poor contact problems of this "golden finger" are caused by some dirty things on it.
If the alarm sound of the PC speaker is not long but short when the computer is turned on, but a short and urgent call, and there is a black screen, then it can be roughly judged that there is a contact problem in your computer memory according to the phenomenon. The solution to poor contact is basically the same as the display card, that is, insert * * * and then insert it. Be sure to insert it to the end when inserting it, and fasten the clips on both sides of the memory module.
SDRAM slots on some motherboards are troublesome, because most of the slots on these motherboards are very tight. If the user encounters this situation, he must not use force. They can press the bottom of SDRAM slot on the motherboard with their fingers, and then press the memory with their thumbs. Hearing a slight noise proves that the memory has bottomed out. Finally, they can fix their memories with clips. There are also some black screens, and the computer will not call the police. At this time, the simplest thing is to analyze the specific problems according to the mathematical "exclusion method".
First, check whether there is any problem with the power terminal board, remove the relevant supporting parts of the computer and replace them with some other equipment that can be used to check whether the power terminal board works normally. If there is nothing wrong with the power terminal board, then check whether the connection between the computer power supply and the motherboard is normal according to the normal procedure, that is to say, check whether the motherboard power supply is normal.
If the socket is not connected by mistake, check whether the power supply is burnt out. If the power supply burns out, the power supply fan will also stop running. In some early computer cases, the power supply was often insufficient. If this problem is suspected, please unplug all power cords from the hard disk, CD-ROM drive and floppy drive, and then restart the computer. After the power consumption rate is greatly reduced, see if this situation is solved.
If the problem still cannot be solved, please rule out that the motherboard BIOS is accidentally damaged by viruses such as CIH, and whether the motherboard is in poor contact or the welding head is short-circuited. In addition to the above, with the continuous improvement of CPU frequency speed, power supply plays an increasingly important role in the whole PC power supply system.
Some people describe the central processing unit as the heart of a computer. Maybe for a long time, we were too concerned about whether the heart is healthy and strong, but neglected the chassis power supply that can provide power and energy for the heart. However, due to the lack of power supply, it may also cause the computer to have a black screen.
The symptom is that you can hear the chassis power fan start normally after starting, but you can't hear the "drip" sound of system error, but the machine doesn't work, there is no self-test process, and a black screen is displayed. If all boards and memories are plugged and unplugged again after cutting off the power supply, make sure that all boards or components are not loose, which is mostly caused by insufficient power supply.
I strongly believe that for your love of computer health, don't ignore the chassis and power supply when buying a computer. Buying a power supply with a rated power of more than 250 watts is a kind of care for your machine. There is one more thing to note here. At present, many power supplies with rated power of 250W on the market simply can't meet the requirements, which leads to another suggestion. Buy power supply and try to take care of famous brands. At this time, the brand is a powerful guarantee for the safety of your machine.
If there are many peripherals installed on your machine, such as dual disks, dual CPUs, dual optical drives, SCSI cards or anything else, you'd better find a more powerful (300~400 watts) or server power supply. As for users of P4, Thunderbird and GeForce3, they must use more than 300 watts of power, otherwise things more troublesome than black screens will emerge one after another.
Of course, the phenomenon of black screen is mostly caused by hard injuries on the PC, but it is not absolutely so. Soft injuries may sometimes be easier to deceive users. In the process of using our computer, some black screen phenomena may also be soft failures after entering WINDOWS 98/WINME/WIN2000 or even WINXP system (but I haven't found the black screen failure of WINDOWS XP yet, but since there is no conclusion, it can be assumed that it also exists).
If users find that the machine is assembled, there are always inexplicable problems in the process of installing operating system and other software, or even a sudden black screen crash. Here, it is necessary for us to eliminate the cause of the virus, because there are many cases in which the virus causes the black screen in the system operation, but the only solution is antivirus, and there is nothing to say.
On the contrary, it is the error or black screen in the operation of the program that should attract our attention.
If the computer monitor can't receive the signal, please ask God for guidance.
Problem analysis:
The computer boot monitor is turned on (the power indicator is on), but there is no signal or the screen shows "No signal". Generally, the memory is loose or oxidized, which leads to poor contact, or the display data line is in poor contact, or the memory, graphics card, display or data line is damaged.
Handling suggestions:
65438+ If you can't operate it, it's easier: just tap or kick the chassis once or twice (note position: the right center of the left and right housings of the chassis without interfaces at the back; Note: don't push too hard, and of course you can't be weak. You may need to repeat the above operation. If it fails, the memory module needs to be replaced. If there are more than two memory chips, you need to test them one by one.
2. If the above operation fails, turn off the power supply and open the chassis, plug and unplug the graphics card again, and plug the data cable between the monitor and the graphics card tightly. If it still doesn't work, consider that the data cable or graphics card is damaged and replace it with a new one.
3. If the monitor is not powered on (the indicator light is off), first check whether the power switch is turned on, then check the back of the monitor, plug in the power cord connected to the monitor (the power cord can be replaced if possible), and check whether the other end of the power cord is powered on the socket.
4. If the host computer can display when it is connected to other monitors, or the local monitor cannot display when it is connected to other normal hosts, the monitor is damaged and needs professional maintenance.
5. What is the reason why the computer monitor can't receive the signal?
The path of computer display is: host → graphics card → signal line → monitor.
Problems with the monitor's inability to receive signals may include:
1. There is something wrong with the input port and input circuit of the monitor, so you can connect other computers to identify it.
2. Whether there is a problem with the signal line itself and the port. For terminals that are frequently plugged and unplugged, especially the pins of VGA port, it is easy to bend or break. For frequently moving signal lines, the core line is also broken from time to time. Check the port, pin and measuring core.
3. The display card is faulty. When the graphics card works on the computer, the burden is heavy and it is easy to be damaged by heat. Common fault phenomena are: a, there is a flower screen, mostly local damage to the display memory. B, intermittent cries when starting the machine, which may be due to poor contact of the pin and rubbing the golden finger. C, the graphics card is damaged, and the host seems to be working. This is different from sending cards to other computer hosts for testing.
4. The mouth is wrong. At present, there may be multiple display sockets on a computer, such as integrated graphics port, independent graphics port and DVI port. Which port should I set? No, either an error is displayed or there is no response.
5. Computer hardware failure. It can be found that the computer self-test failed and there is something wrong with the motherboard.