No signal solution for computer monitors

Follow these steps to troubleshoot:

Displays data Line host connection is loose or has fallen off

Abnormal) the display data line is damaged (this situation is usually rare. Note that the pin is not bent or broken)

Internal problems (such as loose memory, loose graphics card, and poor video output interface) on the computer host ).

If the above solution is the same, we will try again by referring to the following method.

A black screen is displayed on the monitor after it is turned on. No display is displayed, which is a common problem for many computer users. In fact, as long as you have a certain understanding of the working principle of the computer, you can completely eliminate these simple faults that are not damaged by the device.

1. when there is no image display on the black screen of the monitor (however, when there is no signal sent from the host, the screen will display "no signal line connection"), first check whether the host power supply is properly plugged in, does the power supply fan rotate? Is the power indicator and hard disk indicator flashing on the host panel? Because if the host power supply is not working or the motherboard is not powered, the display will not display images if it does not receive signals.

2. Check whether the power supply of the monitor is properly plugged in? If the power switch of your monitor is a touch switch, when you power up the monitor, you should hear a slight "snap" sound, then you can determine that the display switch power circuit is good. Is the power switch of the monitor enabled? Is the power indicator of the monitor on? When you move your hands close to the display screen and see if there is a "squeaking" sound, and at the same time, the sweat on your hands is sucked up, this is checking whether the monitor's high-voltage circuit works properly.

3. If you confirm that the monitor is powered on and there is a high voltage, continue to check whether the data cable connector of the monitor is in good contact with the signal output interface of the video card? Is there any looseness? Unplug the plug and check whether there are bending or broken needles or a large amount of dirt in the D interface. This is a problem that many users often encounter. When connecting the D plug-in, the force is uneven, or the fixed screw of the interface is forgotten to tighten, which causes poor contact, or due to improper installation method or excessive force, the D interface contains a broken or bent needle, resulting in poor contact.

Note: The 15-pin of the data cable plug of the monitor may have pins such as 4, 9, and 11. Normally, do not manually use other wires to fill these pins, to avoid other faults.

Let's talk about it a little more: The first, second, and third needles are red, green, and blue signal input. If the needle is not in good contact, the screen will have a lack of corresponding color.

If there is a problem with the 12th and 15th pins, the host cannot find the corresponding display, but this does not affect the use.

If there is a problem with the pins 13 and 14, a black screen will appear on the monitor, and the indicator lights will change from green to orange after a while. One of the above black screens is displayed.

4. Enable the chassis and check whether the display card is correctly installed? Is it in good contact with the motherboard slot? Does the graphics card or slot occupy too much dust due to a long usage time, resulting in poor contact? Whether the chip on the video card is burnt or cracked. When a black screen is caused by a video card, the computer prompts a four-digit "tick" sound during self-check. When installing the display card, hold the upper part of the display card in your hand and insert the card into the groove uniformly. The fixed screw port of the video card is consistent with the screw port of the trunk box. Do not force fixing when the video is not plugged in, resulting in distortion of the video card. If you confirm the installation is correct, you can remove the video card and use an alcohol cotton ball to wipe the gold finger of the plug-in or use another slot (only for PCI graphics cards) for installation. If not, you can only try another good video card.

If not, consider the compatibility between the video card and the motherboard when you confirm that the video card is complete. You 'd better check the relevant information or ask a netizen.

5. Check whether other boards (including sound card, decompression card, and video capture card) have good contact with the motherboard slot? Check whether the connection between the data cable of the hard disk and the power cord of the hard disk is correct? Replace the slots of other boards and clean the pins. This is often overlooked by many. It is generally considered that the computer black screen is a problem with the display and graphics card, and it has nothing to do with other devices. In fact, the installation of sound cards and other devices is incorrect, which makes it difficult for the system to complete the initial operation. In particular, the hard disk data cable and hard disk power cord are inserted incorrectly, which may cause non-display faults.

6. Check whether the memory stick has good contact with the motherboard? Re-plugging the memory stick once, try another slot, or change the memory stick. If there is a problem with the memory stick, when the computer is started, there will be a continuous rush of "Beep. The tone varies depending on the motherboard.

7. Check whether the CPU is in good contact with the CPU seat on the motherboard? Poor contact between the CPU and SLOT1 plug-in or SOCKE370 socket due to movement or other factors. It is best to manually press the CPU or remove the CPU and reinstall it again.

8. Check whether the jumper or CMOS settings of CPU external frequency, frequency doubling, memory frequency, and so on are correct. Check related jumpers one by one in accordance with the motherboard manual, in the order of "CPU outer frequency jumper-CPU multiplier jumper-memory frequency jumper ".

9. Check whether the CPU voltage is set properly. Be careful when setting the CPU voltage jumper, and be sure to match the CPU voltage. The Steps 8 and 9 should be carefully checked when black screens appear for some assembly machines or users who prefer overclocking.

10. Check whether the CMOS parameter settings are correct. If your computer has two video cards, you set the first initial PCI video card in CMOS, and your only display is connected to the AGP video card, of course, the display will not be bright.

11. Check whether the working environment required by the host and display meets the requirements? Whether the operating voltage is normal and the ambient temperature is too high. In addition to checking according to the above steps, you can also quickly locate the computer based on its working conditions. For example, after the host is powered on, you can hear a "success" message indicating that the computer has completed self-check, if the hard drive indicator is flashing continuously at this time, check in step 2 to step 4.

12. If the display displays content during the startup of the computer, but a black screen appears after the WIN98 screen is loaded, this is only a problem with WIN98 system software.