Check whether the data cable is loose or damaged. If it is loose, tighten it. If it is not loose, find a new data cable to test; If there is no problem with the cable, the problem may be on the host; If it is an independent graphics card host, you can plug the independent graphics card or memory module again.
Check whether the data cable is loose or damaged. If it is loose, tighten it. If it is not loose, find a new data cable to test; If there is no problem with the cable, the problem may be on the host; If it is an independent graphics card host, you can plug the independent graphics card or memory module again; It may also be the cause of static electricity on the motherboard. You can unplug the power cord of the host and press the switch button of the host to release static electricity.
1、 Cause of no signal on computer monitor
1. The connection of the display data cable to the host is loose or has fallen off.
2. The data line of the monitor is damaged (this situation is generally rare, mainly pay attention to whether the pins are bent or broken).
3. Computer host internal problems (such as memory module loose, graphics card loose, poor video output interface, etc.).
2、 The solution of computer monitor without signal
1. Check whether the data connection cable is loose or damaged, and tighten it if it is loose. If not, find a new one to test.
2. If it is an independent graphics card, the graphics card loose will also have similar problems, it is recommended to re install the next graphics card to solve the problem.
3. Computer memory module loose or too much dust, resulting in no signal display. The most obvious situation is that everything inside the computer seems to be working normally, but the display has no signal. This kind of problem is often found in computers that have been used for a long time, and it is likely that dust has not been cleaned up for a long time. The solution is to take out the memory module, clean the golden finger of the memory module with a paper towel, and then install it back.
4. If the power dissipation of the on-board power circuit is reduced, the power supply of the graphics card is insufficient, and the capacitor leakage is serious, which leads to the voltage reduction of the corresponding power circuit, resulting in no signal. You can disassemble the host, find the battery, buckle it out, leave it for a few minutes, discharge it, and then install it again.
5、如果上述方法依然无法解决，就要考虑是不是主板静电的原因了。解决办法：拔掉主机电源线，长时间按住主机开关按键（大约持续 3-5 分钟），然后插上电源线开机试试，一般都可以解决。
5. If the above method is still unable to solve, it is necessary to consider whether the motherboard static. Solution: Unplug the power cord of the host, press and hold the switch button of the host for a long time (about 3-5 minutes), then plug in the power cord and start the machine. Generally, it can be solved.
3、 Analysis of common faults of computer monitor
1. Black screen
When you turn on the computer, after a few minutes, there is no image. At this time, you should first check whether the power indicator on the display panel is on. If it doesn’t light up, check whether the power plug of the monitor is connected properly. If the power cord is well connected (to ensure that the power socket has power, try changing a jack), and the power switch is on, but the indicator light of the display is not on, it indicates that there is a fault in the internal circuit of the display. At this time, it should be sent to a special maintenance department for repair.
如果显示器的电源指示灯亮，这时应该重新启动电脑，并注意主机的指示灯是否闪亮，主机里是否有“嘀”的一声。如果有说明电脑已经正常启动。这时应检查显示器与主机的信号线连接是否正常，和主机相连的 15 针 D 形插头是否松动，插头内的针是否有断、歪、短等情况。如果连接正常，说明显示器内部有故障，应送修。
If the power indicator of the monitor is on, you should restart the computer at this time, and pay attention to whether the indicator of the host is flashing, and whether there is a “beep” in the host. If so, the computer has started up normally. At this time, check whether the signal line connection between the display and the host is normal, whether the 15 pin D-shaped plug connected to the host is loose, and whether the pin in the plug is broken, crooked, short, etc. If the connection is normal, there is a fault inside the display and it should be sent for repair.
The energy-saving display will automatically work in the corresponding state and mode according to the line field synchronization signal sent by the host, and the indicator light on the panel indicates the corresponding state at the same time. It is usually orange flashing – shutdown or sleep, orange – suspend, yellow – wait, green – normal display.
When the display screen is black, after careful inspection, it is not the fault of the host. At this time, it is better not to power on the display continuously or for a long time, so as to avoid the expansion of the fault.
2. Flower screen
通常是由于显示器不支持主机送来的显示模式，往往是高于显示器的显示模式，引起屏幕的图像混乱，无法看清楚屏幕上的图像和文字。如果是具有模式自动识别的显示器，有可能是黑屏状态，但这时面板下方指示灯为绿色。这时可以重新启动电脑进入安全模式，把显示模式改为 640*480 后，再次启动电脑即可恢复。如果这种方法不行，可以在安全模式下把显卡驱动程序删除，然后在正常模式下重新安装显卡驱动即可。还有在显卡的显存发生故障时会出现屏幕上固定位置显示混乱，而其他地方却显示正常。也有个别的显卡损坏造成花屏的，但这种情况几率很小。
Usually because the display does not support the display mode sent by the host computer, it is often higher than the display mode of the display, which causes the image confusion of the screen and makes it impossible to see the image and text on the screen clearly. If it is a display with automatic pattern recognition, it may be in black screen state, but the indicator light at the bottom of the panel is green. At this time, you can restart the computer to enter the safe mode, change the display mode to 640 * 480, and then restart the computer again. If this method does not work, you can delete the graphics card driver in safe mode, and then re install the graphics card driver in normal mode. In addition, when the display memory of the graphics card fails, the fixed position display on the screen will be confused, while the display in other places will be normal. There are also individual graphics card damage caused by the splash screen, but the probability of this situation is very small.
The more obvious is the lack of red or yellow, or blue, may also be color confusion, but the image details are clear. At this time, if the monitor looks a little longer, the eyes will feel uncomfortable and tingling. At this time, you can check the plug between your monitor and the host after the power is turned off to see if the pin inside is broken, and then check whether the graphics card is loose. If there are no problems, the monitor can be sent for repair.
When red (R), green (g) and blue (b) appear on the screen, the internal circuit of the display must be broken.