How to troubleshoot the motherboard

PC computer, because the motherboard problems caused by the crash, blue screen and other failures are not uncommon, the incidence rate is generally higher. There is a problem with the motherboard, on the one hand may be due to driver installation error or loss caused by soft fault, on the other hand, due to the board of some of the capacitor aging or damaged, resulting in hardware failure. If the motherboard has a hardware failure, we generally start from the judge of the motherboard on the capacitor components have no damage to start the step-by-Step troubleshooting and maintenance, if a capacitor damage, we need to replace the same model of the capacitor that can solve the fault. However, there are also some time is not necessarily due to capacitor damage caused by the motherboard failure, such as the South, North Bridge, such as the failure of the chip burned often, and this kind of fault occurs due to the motherboard heat dissipation, static electricity and improper operation caused. Therefore, we troubleshoot the motherboard, we should be particularly careful, according to the cause of the fault carefully analysis of the problem, and finally found the root cause of the failure and exclusion.





first, the motherboard deformation causes the computer not to start the malfunction analysis and the elimination





failure phenomenon: A computer room suddenly can not start. The starting phenomenon is: The computer in the self-test process appeared "a long three short" tweet. Obviously, this is the failure of the video card (the motherboard is the award BIOS). Open the chassis and press the video card again. Start the computer, the fault remains. is the video card broken? Remove the video card and plug it into another computer, and the computer starts normally. Another normal video card is plugged into the machine, the phenomenon reappears.





fault analysis and Troubleshooting: is the motherboard out of the problem? The motherboard's AGP slot is carefully observed with a magnifying glass and no abnormalities are found. In order to check whether it is contact unexpectedly, the graphics card repeatedly unplugged several times, respectively, with different intensity, so that the overall and both sides of the video card into different depths into the slot. When the test to the video card has an interface to the micro-tilt up, with a crisp and clear short, lovely blue sky and white clouds finally appeared in front of me. After testing the video card again, the computer can not start.





find the reason, so in the installation of video card, in the baffle gasket under the pad about 1.5 mm thick hard paper, tighten screws, the computer normal use. After the induction of the following reasons: Because the number of computer room doubled, in order to save money, the computer table from a seat changed to two seats. After the transformation of the seat can not be vertical chassis vertical, only to wronged them flat. But the side of this plane has a 2 cm high baffle, so that the computer placed in a tilt angle, long-term down, the motherboard deformation, resulting in graphics card and slot can not be very good contact. It seems that the computer placement is not insignificant, if placed improperly, so that the motherboard deformation, will produce a variety of failures.





Second, the computer frequently crashes really fierce is the North bridge chip heat dissipation bad





fault phenomenon: A computer in use, the recent occurrence of frequent panic phenomenon. Initially thought to be infected with the virus, after the killing did not find any virus. It is also believed that the hard disk is too fragmented, causing the system to be unstable. However, the problem is still unresolved after defragmenting the hard disk. Unfortunately, the format of the system disk, reinstall the system, but the problem is still unresolved, seriously affecting the day-to-day work.





Failure Analysis: After the installation of the system failure did not rule out, it seems that the hardware appears to be a problem. Just beginning to suspect a memory failure. However, the failure remains unresolved after replacing the memory strips. So where does the problem come from? With careful analysis, the motherboard is the most likely to fail, since there is no memory problem.





then uses the substitution method, after replacing the motherboard, turns on the computer to carry on the test, the breakdown disappears, appears the problem origin on this motherboard. This is a motley 865PE chipset motherboard, the main board of materials used to work quite generally. Careful inspection, found that the motherboard on the capacitor and no breakdown of the phenomenon, the entire PCB board also did not leave traces of burning, so in the end is the motherboard which part of the problem. The motherboard is then again cleaned and then mounted again into the computer to access various devices. After the start of the last half of the phenomenon of the crash, then hand touch the motherboard North Bridge chip on the heatsink, found very hot, it appears that the problem is the above. So bought a fan with the radiator, after a toss, finally replaced, and will replace the North Bridge heatsink installed in the south-South chip. (A motley Motherboard South bridge chip completely exposed outside, did not install any heatsink.) ）




After the beginning of the
after a test, the fault completely ruled out, after careful analysis, just understand the cause of the failure. The original machine is in the winter match, the temperature is low and did not have much effect, then the problem will be exposed after the summer.





Failure Summary: This kind of problem, in general, will first consider the memory bar. However, due to the motherboard cache problems or the motherboard design heat dissipation is also prone to frequent panic phenomenon. The author on a brand 845PE motherboard has found that due to the motherboard cooling is not good enough to cause the failure. After the crash, touch the CPU around the motherboard components, found that the temperature is very high and hot. After the replacement of high-power fan, the crash can be resolved. For cache problems, you can enter the CMOS Setup program, the cache will be prohibited after the smooth resolution of the problem, of course, the cache is prohibited after the speed that will certainly have an impact.





Third, the motherboard failure analysis and elimination of power supply





Fault Performance: The author of Athlon XP 1600+, the Czech Republic 333 motherboard, 256MB modern DDR 266 memory, cool fish 4 generation 80GB hard disk, Ati RADEON le video card and DVD, CD-ROM of the assembly machine, the use of more than three years all normal, But lately there have been problems. The modem drop-line situation occurs in the poor quality of the line, system failure, and so on. However, recently I encountered the drop line is quite bizarre, the final source of the problem from the motherboard.





the author has been using external modem Internet, although it is an earlier model of the product, but outstanding quality, three years has been working normally. A few days ago due to work busy, three days without a computer, a day to go online to check the news. Dial-up very smooth, but after browsing the Web page for 10 minutes, suddenly disconnected, began to think that the normal idle state was kicked out of the service, did not care, but next to almost every time the automatic drop line.　　So I switched to another dial-up phone, access to the network after an hour has not lost the line, the heart of a lot of sureness. Failure analysis and elimination: The next day, the same problem occurred again, this time no matter how many access numbers are not useful. Think of the use of the modem three or four years, may be the longevity is sleeping, so decided to buy a new modem the next day. Evening reading the newspaper, family suddenly a voltage instability caused my attention, I suddenly think of this computer PS2 keyboard interface will often appear contact bad situation, will have something to do with this?





with doubt, I took out the tool to remove the motherboard and set up a system temporarily, with a multimeter a little bit of measurement voltage, unexpectedly found Backplane USB interface, printer, COM interface and mouse keyboard PS2 interface have power shortage situation, a little to the motherboard afterburner twisting, and sometimes can restore voltage supply. Continue to find the results, finally found in the I/O interface part of the coupling circuit is virtual welding, so the next day with the help of friends, repair the virtual welding coupled circuit. At this point, the modem dial-up Internet has returned to normal, there is no automatic disconnection thing.