1. Check whether the interface and power cord of the chassis power supply are in good condition. If the interface and power cord are damaged or broken, they should be replaced in time.
2. Check the socket of the motherboard power cord. If there is no damage, pulling out the socket and plugging it in can generally solve the problem that the motherboard has no power supply due to poor contact.
3. Check the power supply of the chassis. We usually use the substitution method to test, that is, box the power supply to another computer and try it. In fact, you can detect the quality of the power supply without changing people. First, you turn on the ATX power supply, and then use a pin to connect the ATX power supply to the green line and any black line of the motherboard power interface. If the power supply is normal, its fan will turn. If the fan doesn't turn, there is something wrong with the power supply.
4. Check the switch on the chassis power supply to see if it is correctly connected to the motherboard. As shown below, check the jumper on the motherboard, find the jumper that controls the power supply, and try to short the jumper pin. If the motherboard can work normally, there is something wrong with the jumper pin (mainly because the jumper pin and jumper cap are not in good contact, so shortening the jumper pin can make them completely coupled).
Note: Be careful not to let the motherboard touch the metal chassis during operation. Generally, we take the motherboard and power supply out of the chassis and put them on bad conductive objects (such as wooden desktops). , as shown in the figure, plastic desk). If static electricity is introduced, it is easy to cause short circuit of the motherboard. So pay special attention to this.
There is electricity, but the display screen is still black.
1. Check all cards (video card, sound card, etc. ), whether the CPU and memory module are in place (whether they are in good contact). The clumsy way is to pull them out and plug them in again. The advantage of dealing with the black screen in this way is to eliminate the problems one by one. "It's better to kill a thousand than to miss a thousand" is our purpose of checking the problem.
2. If the problem is too serious, you have to use the most "cruel" trick: unplug all secondary original components and disconnect all secondary power cables, including IDE, floppy drives and other equipment; What you need is the most basic initial startup self-check screen: such as memory, motherboard, CPU, graphics card and so on. Through, other components are added one by one, and each self-check is added; If the self-check fails, you will find out your problem, and the problems such as incorrect installation or incompatibility will be solved.
3. If you have money, you can also buy a post diagnosis card (for power self-inspection). POST card can identify the cause of system crash at startup. With the POSq diagnostic card, you can find the problem in time through the indicator light on it.