1. When there is no image on the display screen (however, when there is no signal from the host, the display on the market will display "No signal line connection" on the screen. First, check whether the power supply of the host is plugged in and whether the fan of the power supply is rotating. Are the power light and hard disk light flashing on the host panel? Because if the host power supply doesn't work or the motherboard doesn't supply power, of course, the monitor won't receive the signal and there will be no image display.
2. Check whether the power supply of the monitor is plugged in. If the power switch of your monitor is a touch switch, you should hear a slight "beep" sound when you power up the monitor, so you can judge that the switching power supply circuit of the monitor is good. Is the redisplayed power switch turned on? Is the power indicator light on the monitor? When the hand is close to the monitor screen, move it slowly to see if there is a hissing sound, and at the same time, the hair on the hand feels sucked up. This is to check whether the high-voltage circuit of the monitor works normally.
3. If it is confirmed that the monitor is powered on and generates high voltage, continue to check whether the data cable connector of the monitor is in good contact with the signal output interface of the graphics card. Is it loose? Pull out the plug again and check whether there are bent or broken needles or a lot of dust in the D- connector. This is a common problem of many users. When connecting the D-type socket, the force is uneven, or the interface fixing screw is forgotten to tighten, which makes the interface loose and causes poor contact, or the D-type interface has broken or bent needles due to improper installation method or excessive force, which causes poor contact.
Note: The 15 pin of the monitor data cable plug may be missing, such as 4, 9, 1 1 pin. At this time, it is perfectly normal. Never artificially use other wires to supplement these missing pins, so as to avoid other faults.
In detail: 1, pins 2 and 3 are red, green and blue signal inputs. If any pin is poorly contacted, the screen will lack the corresponding color.
If there is something wrong with pins 12 and 15, the host can't find the corresponding display, but this will not affect the use.
If there is something wrong with pins 13 and 14, the display will have a black screen, and the indicator light of the display will change from green to orange after being turned on for a period of time. One of the above black screens appears.
4. Open the chassis and check whether the monitor card is installed correctly. Is it in good contact with the motherboard slot? Does the graphics card or slot accumulate too much dust because it is used for too long, resulting in poor contact? Whether the chip on the graphics card is burnt or cracked. When there is a black screen due to the graphics card, there will be a short and long "beep" sound prompt when the computer starts self-checking. When installing the video card, hold the upper part of the video card by hand and insert it into the card slot evenly and forcefully, so that the fixed screw hole of the video card matches the screw hole of the main chassis. Don't fix it forcibly when it is not plugged in, which will cause the graphics card to deform. If the installation is correct, you can remove the graphics card, wipe the gold finger of the pin with an alcohol cotton ball, or install it in another slot (only for pci graphics cards). If not, you can only try a good graphics card.
If not, consider the compatibility between the graphics card and the motherboard when making sure that the graphics card is in good condition. It's best to check the relevant information or ask netizens.
5. Check whether other boards (including sound card, decompression card and video capture card) are in good contact with the slot of the motherboard. Pay attention to check whether the data cable of the hard disk and the power cable of the hard disk are connected correctly. Replace the slots of other boards and clean the pins. This point is often easily overlooked by many people. It is generally believed that the black screen of the computer is a problem of the monitor and graphics card, and has nothing to do with other devices. In fact, due to the incorrect installation of sound cards and other equipment, it is difficult to complete the initial initialization of the system, especially when the data cable of the hard disk and the power cable of the hard disk are inserted incorrectly, which can easily lead to the failure of no display.
6. Check whether the contact between the memory module and the motherboard is good. Plug and unplug the memory module again, or try another slot or replace it with a new memory module. If there is something wrong with the memory module, there will be a continuous and rapid "beep" sound when the computer starts. The tone of different motherboards will be different.
7. Check whether the cpu is in good contact with the cpu seat on the motherboard. Poor contact between cpu and slot 1 socket or socke370 due to movement or other factors. It is best to hold down the cpu by hand or remove the cpu and reinstall it.
8. Check whether the settings of cpu external frequency, frequency multiplier and memory frequency jumper or cmos are correct. Check the related jumpers one by one according to the motherboard instructions, and the sequence is "cpu external frequency jumper -cpu frequency multiplier jumper-internal frequency jumper".
9. Check whether the voltage of cpu is set correctly. Be careful when setting the cpu voltage jumper, and it must be consistent with the working voltage of the cpu. For some assembly machines or users who like overclocking, check carefully when there is a black screen.
10. Check whether the cmos parameters are set correctly. If your computer is equipped with two graphics cards, you set up the first pci graphics card in cmos, and your only monitor is connected to the agp graphics card. Of course, the monitor won't light up.
1 1. Check whether the working environment required by the host and monitor is satisfied? Whether the working voltage is normal, whether the ambient temperature is too high, etc. In addition to checking according to the above steps, you can also quickly locate the computer according to its working state. For example, after turning on the power of the host, you can hear a beep, indicating that the computer self-test is completed. If the hard disk indicator is flashing at this time, it is necessary to check it in the second to fourth steps.
12. If the monitor displays contents during the computer startup process, but a black screen appears after loading the screen of win98, it is just that there is something wrong with the win98 system software.
The above inspection method is based on the fact that there is no electrical fault in the monitor itself, that is, the power indicator light of the monitor changes from green to yellow after the host power is turned on, but no image is displayed on the black screen of the monitor. If the monitor still does not display after using the above steps, please ask a professional to repair it.