Computer Motherboard Troubleshooting Methods

The First: Cleaning method

If there is conductive debris on the motherboard, as long as brush lightly with brush to the motherboard on the dust can be, the motherboard on some cards, chips are used in the form of pins, often because of the pin oxidation caused by poor contact, we just use the eraser to surface oxidation layer, and then plug the problem solved.

　　Second: The observation of the law

In the event of failure, you can carefully observe the problem of the motherboard, to see whether each plug, socket tilt, resistance, capacitance of the pin is not mutually connected, the surface of the chip is burnt or cracked, the motherboard on the foil is burning traces appear. In addition to check that there is no foreign body into the motherboard components, encountered do not understand where the use of multimeter to measure.

　　The third type: plug-and-swap method

Host failure causes many, the most direct way is to shut down the case of the card block pull out, each pull out a card after the boot to observe the operation of the machine, if the computer after pulling out a block card is normal, the reason is that the card is faulty or the corresponding I/O bus slots and load circuit problems. If the computer does not boot up after all the cards are unplugged, the failure is likely to be on the motherboard. At this point can be used to plug the Exchange method in essence will be the same model plug-in board, bus mode, the same function of the card or the same model of the exchange of chips, according to the changes in the fault diagnosis. This method is used for easy to plug the maintenance environment, for example, there is a self-test time error, you can exchange the same memory chip or memory to determine the cause of the failure.

　　Fourth: Measuring method of resistance and voltage

For insurance reasons, you should measure the resistance value between the power +5v and the ground (GND) on the motherboard. The simplest way is to measure the resistance between the chip's power pins and the ground. When not plugged in, this resistor is generally 300ω, and the lowest is not less than 100ω. Again the reverse resistance value, there will be differences, but not too big difference. If the positive and negative resistance are very small or close to the conduction, it is indicated that there is a short-circuit on the motherboard, should check the cause of the short circuit. When troubleshooting the short-circuit, plug in all the I/O cards to measure whether the +5v,+12v and the ground are short. In particular, whether the +12v and surrounding signals collide. If you have exactly the same type of motherboard on hand, you can also use the method of measuring resistance to measure the doubt on the board, by contrast, you can quickly find the chip fault.