2, the display itself
black failure failure caused by a, the AC power is insufficient
external source power is insufficient, resulting in some old display or some large power consumption does not start the monitor, a display One of the causes of black screen failure caused by its own fault. Or the external power supply voltage is unstable, and the voltage is too high or too low, which may cause the display to work unstable or even not working.
b, circuit switching power supply circuit failure
display and other circuit failure is the main cause of failure causes the display black. If the fuse is blown, the rectifier bridge switch is broken, and the current limiting protection resistor is blown, causing the display to fail.
C, tubes, damage to the horizontal output circuit
tube or line output circuit failure will lead to a black screen display power fault no raster, black display is caused by the major causes of failure.
2, black failure
computer software failures caused by software conflicts, such as the driver improperly installed, BiOS refresh error, CMOS settings are not correct and so can cause black screen failure. In addition, hardware damage such as CIH caused by a vicious virus may cause a black screen failure of the display. If you can think about the cause of the fault when you go to this kind of fault, you can solve the fault and know that it is half the effort.
3, display a black screen troubleshooting ideas
a, check the host power supply is working properly. First, determine if the host system has received power supply by looking at the power indicator of the main unit chassis panel and whether the power supply fan is rotating. Secondly, use a multimeter to check whether the external voltage meets the requirements. If the voltage is too high or too low, it may cause overvoltage or undervoltage protection of the host power supply. In addition, it is important to check the quality of the power switch and reset button and the correct connection between them and the motherboard. Because the power switch and reset button on many inferior chassis often occur after several times of use, it will cause damage. The black screen of the machine is not displayed. If the power supply is damaged, you can solve the problem by replacing the power supply.
b, the monitor checks whether the power supply connected. When the display is powered on, there is a “beep” sound, and the power indicator of the display is on. When the user moves to the display screen, there is a “beep” sound, and the back of the hand is erected.
c, check the monitor signal line contact is good and the display card. If there is a lot of dirt at the interface, broken needles and other damage will lead to poor contact and the display will be black.
d, display card check is good contact with the motherboard. If the display is black and the speaker inside the main unit emits a short beep, it indicates that there is a problem with the connection between the display card and the main board, or there is a problem with the connection between the display card and the display. It is important to check whether the slot contact is good. If there is any foreign object in the slot, change the display card to a motherboard slot for testing to determine if there is a problem with the slot.
e, check whether the display card to work properly. Check whether the chip on the display card can burn, the crack marks and the cooling fan on the display card work, and the heat dissipation performance is good. Change to a working card to check if the card is damaged.
f, the contact with the motherboard memory check is good, whether the memory of excellent quality. If the computer starts up with a black screen and the host emits a continuous beep, it indicates that there is a problem with the memory module. You can focus on checking the installation and contact of the memory and the memory slot, re-plugging the memory module once, or replacing the new memory module.
g, the check box fan spins. If the cooling fan inside the chassis is damaged, it will cause poor heat dissipation. In severe cases, the CPU and other components may be damaged or the computer will automatically stop and protect, and an alarm sounds.
h, check other boards (such as sound cards, decompression card, a video capture card) attached to the board slot is good, and the drive signal line is correct. This is often overlooked by many people. It is generally believed that the black screen of the computer is a problem in the display part, and has nothing to do with other devices. In fact, due to the incorrect installation of sound card and other equipment, the system initialization is difficult to complete, especially the data line interface of the hard disk, and it is easy to cause no display failure.
i, checks whether the CPU overclocking, in contact with the motherboard is good CPU, CPU cooling fan is intact. If overclocking results in a black screen, then the CPU will jump back to the original frequency. If the contact is poor, remove the CPU and reinstall it, and use a high-quality high-power fan to dissipate heat from the CPU.
j, check the parameter settings. Check if the CMOS parameter settings are correct. If the CMOS parameters are set incorrectly and cause a black screen, and the computer does not start, you must open the chassis and restore the CMOS default settings.
k, to check whether the virus caused a black screen. If the monitor is black because of the virus, you can use the latest version of anti-virus software for processing, sometimes you need to rewrite the BiOS program.