1. Software
1. Virus
The "Shockwave" virus also prompts the system to restart automatically after 60 seconds.
The Trojan horse program controls all the activities of your computer from a remote location, including making your computer reboot.
Remove the virus, Trojan, or reinstall your system.
2. System file corruption
System files are corrupted, such as KERNEL32.DLL under Win2K, fonts under Win98 FONTS directory, and other essential system runtime files are corrupted, and the system will not be able to complete the initialization and forced to reboot at startup.
Solution: Overwrite the installation or reinstall.
3. Timing or scheduling software
If you set up a taskbar to restart or load certain programs, the computer will start up again when the time comes. In this case, we can open the "Startup" item, check if there are any unfamiliar executable files or other timed programs, and block them before booting the computer. Of course, we can also enter "Msconfig" command directly into "Run" to select the startup items.
Second, the hardware
1. chassis power supply power, DC output is not pure, dynamic response is slow.
Users or installers often do not pay attention to the power supply, the use of inexpensive power supply, so it is one of the biggest suspects causing the system to restart automatically.
①Power supply output power is insufficient, when running large-scale 3D games and other software that take up CPU resources, the CPU requires high-power power supply, the power supply power is not enough and overload caused by power protection, stop output. After the power supply stops output, the load is reduced, at which time the power supply starts again. Because the protection/recovery time is very short, so the performance to us is the host automatically reboot.
②Power supply DC output is not pure, digital circuits require pure DC power supply, when the DC output of the power supply in the harmonic content is too large, it will lead to digital circuits work error, the performance of the frequent crash or reboot.
3 CPU workload is dynamic, the current requirements are also dynamic, and requires a rapid dynamic response. Some poor-quality power supplies have long dynamic response times, which can also lead to frequent crashes or reboots.
④Updating equipment (high-end graphics cards/large hard drives/video cards) and adding equipment (burners/hard disks) with power exceeding the rated output of the original power supply can lead to frequent crashes or reboots.
Solution: Now replace the high-quality high-power computer power supply.
2. Poor thermal stability of the memory, chip damage or setup errors
Memory problems lead to system reboot to the system reboot the chances of a relatively large.
1) Poor thermal stability of the memory, boot can work normally, when the memory temperature rises to a certain temperature, it can not work properly, resulting in crash or reboot.
② When the memory chip is slightly damaged, the boot can pass the self-test (set the fast startup does not fully detect the memory), you can also enter the normal desktop for normal operation, when running some of the I/O throughput software (media playback, games, graphic/3D graphics) will reboot or crash.
Solution: Replace the memory.
③Setting the CAS value of the memory too small can also lead to memory instability and cause the system to reboot automatically. It is generally best to use the BIOS default settings and not to change them yourself.
3. The CPU temperature is too high or the cache is damaged
①The CPU temperature is too high, which often leads to a protective auto reboot. The reason for the high temperature is basically due to the chassis, poor CPU heat dissipation, poor CPU heat dissipation reasons are: heat sink material thermal conductivity is low, heat sink and CPU contact surface between the foreign body (mostly for the warranty post), the fan speed is low, the fan and the heat sink accumulates too much dust and so on. There are P2/P3 motherboard CPU below the temperature probe damage or P4 CPU internal temperature measurement circuit damage, motherboard BIOS has a BUG in a special condition temperature measurement is not allowed, CMOS set in the CPU protection temperature is too low, etc. will also cause protective reboot.
②The CPU internal first and second level cache damage is a common CPU failure. If the damage is minor, you can still boot up and enter the normal desktop for normal operation, but when running some software with high I/O throughput (media playback, gaming, graphic/3D drawing), you will reboot or crash.
Solution: Shield the second level cache (L2) or first level cache (L1) in CMOS, or replace the CPU to rule it out.
4. AGP graphics card, PCI card (network card, cat) caused by automatic reboot
① external card workmanship is not standard or poor quality, triggered by the AGP / PCI bus RESET signal malfunction caused by the system reboot.
②There are also instances where the graphics card and network card are loose, causing the system to reboot.
5. The parallel port, serial port, USB interface access to faulty or incompatible external devices automatically reboot]
①The external devices are faulty or incompatible, such as the printer's parallel port is damaged, a pin shorted to the ground, the USB device is damaged, shorted to the ground, the pin definition, the signal level is incompatible, and so on.
2 ② hot plugging external devices, jitter is too large, caused by the signal or power supply momentary short circuit.
6. The internal circuitry of the optical drive or chip damage
Optical drive damage, most of the performance is unable to read the disk / disk. There are also cases where the internal circuitry or chip is damaged causing the host to reboot suddenly during operation. The optical drive itself is poorly designed and FireWare is buggy, which can also cause a reboot when reading a CD.
7. Chassis front panel RESET switch problem
The chassis front panel RESET button is actually a normally open switch, the RESET signal on the motherboard is a +5V level signal connected to the RESET switch. The moment the switch is closed, the +5V level conducts to ground, the signal level drops to 0V, triggering a system reset and reboot, and the RESET switch returns to the normally open position, at which point the RESET signal returns to the +5V level. If the RESET key is damaged, the switch is always in the closed position, the RESET signal is always 0V, the system can not power up and self-test. When the RESET switch elasticity is weakened and the button is not easy to pop up when pressed, the switch will be easy to close with a slight vibration. This leads to system reset reboot.
Solution: Replace the RESET switch.
There is also a short circuit of the RESET switch lead in the chassis, which leads to an automatic reboot of the host.
8. Motherboard failures
Instances of motherboards causing automatic reboots are rare. Generally, the circuits related to RESET are faulty; the sockets and slots have false soldering and poor contact; individual chips, capacitors and other components are damaged.
Three, other reasons
1. utility voltage instability
①Computer switching power supply operating voltage range is generally 170V-240V, when the utility voltage is lower than 170V, the computer will automatically restart or shutdown.
Solution: add a voltage regulator (not UPS) or 130-260V wide switching power supply.
②Computer and air conditioning, refrigerators and other large power consumption appliances *** with a plug board, when these appliances start, the voltage supplied to the computer will be greatly affected, often manifested in system reboot.
The solution is to separate their power supply lines.
2. Strong magnetic interference
Don't underestimate the electromagnetic interference, many times our computer crash and reboot is also due to the interference caused by the interference both from the chassis inside the CPU fan, chassis fan, graphics card fan, graphics card, motherboard, hard disk interference, but also from the outside of the power line, inverter air conditioning and even automotive and other large equipment interference. If our host's interference performance is poor or poor shielding, there will be a host of unexpected restart or frequent crash phenomenon.
3, AC power lines connected to the wrong
Some users of the zero line of the power supply line directly to ground (not go to the zero line of the meter), resulting in automatic restart, the reason for the introduction of interference signals from the ground.
4. Poor quality of the plug or power outlet, poor contact.
Power socket after a period of time, the reed elasticity is slowly lost, resulting in poor contact between the plug and the reed, resistance is constantly changing, the current with the ups and downs, the system will naturally be very unstable, once the current does not reach the minimum requirements of the system to operate, the computer reboot. The solution, buy a good quality socket.
5. Too much dust leads to short-circuiting of the motherboard's RESET line, causing an automatic reboot.
Four, part of the example
1. CPU L2 cache bad example
A few years ago the configuration of the compatibility of the machine: K6-2 200MHz CPU, the use of the VX-Pro + chipset motherboard, two 16MB 72-line EDO memory,
Windows 98 operating system. It automatically rebooted after the blue sky and white clouds screen appeared, and the safe mode was also inaccessible, and could only enter MS-DOS mode. I guess because of the quality of the memory stick to cause the computer to restart the possibility of larger, so first replace the same type of memory stick test, the fault is still the same. Then replace the power supply still can not solve the problem. The last elimination of the motherboard, CPU and graphics card, tried the graphics card after no problem, struggling to find the old motherboard can not install K6-2 200MHz CPU can only be stopped.
At that time, I also suspected that the BIOS settings might be incorrect, and I tried restoring them to their defaults, but that didn't solve the problem. After a few days, when I was fiddling with the computer again, I entered the BIOS and set the CPU Internal Cache to Disable, saved the settings and restarted the computer, and the system was able to boot up! It was estimated that there should be a problem with the CPU cache, so I set the cache to open and started the computer again, and sure enough, the system didn't start up normally again. Due to the cache will be closed after a substantial reduction in CPU performance, so Windows 98 in the startup and run the program much slower than before, and finally replaced a CPU to solve the problem
2. Power failure examples
I work in the place where computers are open every day (because of the number of people surfing the Internet), ten days and a half months without shutting down the machine is a common occurrence. In such a high intensity of work, the failure rate of hardware equipment is also very high.
Failure phenomenon: two compatible machines, a CPU for the Athlon XP 1700 +, a CPU for the P4 1.7GHz, the host power supply are Century Star power. When the computer is running at full capacity for a period of time (at this time, the CPU utilization rate remains at 100%, the hard disk is also a large number of read and write data), often automatically restart. One of them was under-powered when hooking up a 60GB hard disk and an 80GB hard disk.
Failure analysis and treatment: As these two computers are usually used for document editing, Internet and other general work is normal, only when a large number of computers out of the problem. Beginning to suspect that the CPU temperature is too high, but the test shows that the temperature is normal. Check the hard disk found that one of the hard disk bad sectors, but in the replacement of the hard disk reinstallation system failure remains, it seems that the hard disk bad sectors is likely to be the computer is often abnormal reboot caused by. After replacing the power supply with a new one, the problem disappeared.
Disassembled two old power supply, found that one of the power supply two of the same type of electrolytic capacitors (3300μF/10V) at the top of the yellow-brown granular condensation, another power supply two different types of electrolytic capacitors (1000μF/16V, 3300μF/16V) at the top of the yellow-brown granular condensation, which is capacitor breakdown leakage of the liquid caused by the breakdown. In the electronic market to spend money to buy the same type of capacitor replacement, after testing are back to normal. Here to remind, don't put the capacitor positive and negative poles reversed! Afterwards, the analysis found that the author's unit grid often due to overhaul or improper use of electricity, resulting in sudden power outages, resulting in accessories on the capacitor was struck, a motherboard has also been in a sudden power outage after the strike, the inspection found that a few large electrolytic capacitors were struck by the leakage of liquid, replace capacitors back to normal.
3. Graphics card poor contact instances
Fault phenomenon: Friends of the computer configuration for the BenQ BenQ 77G display, Gigabyte 8IRX motherboard, P4 1.6G CPU, 80G hard disk, the small ShadowBlade speed with 3000 graphics cards, all the way to the polar cloud waterfall inside the cat, the motherboard comes with the AC97 sound card. Because of the renovation of the house, to move the computer, the computer after the cable are removed. Later, after connecting the cable themselves, the computer but how can not start up. Computer self-test is normal, flashed the motherboard LOGO, WINDOWS 98 startup screen, then the cursor flashes, everything is normal, but about the time when the system is about to enter the computer, the computer suddenly "tick" a restart, restart a few times are so.
Failure Analysis: The author's friend is a pure "rookie", the initial judgment may be a general wiring problem, it is likely that the mouse and the keyboard is connected to the reverse lead. First of all, check the computer wiring once again, no problem, will not be loose wiring? The first thing I'd like to do is to get all the computer wires connected again
The problem is still there. The first thing I did was to check the CPU temperature in the BIOS after reboot, and it was within the normal range, so I excluded the reboot due to the overheating of the CPU. Friends did not install new hardware, so exclude the power supply is insufficient to cause reboot phenomenon.
Troubleshooting: Ask your friends what operations were performed on the machine before the failure. My friend said that before the removal of the machine has been used very well, no new software has been installed. There is no trace, only from the above four possible causes of failure in the investigation. After reboot, enter safe mode, run msconfig command, remove the startup items that are not necessary for the operating system, reboot, the failure remains. It doesn't seem to be caused by the software installation. Next, let's see if the resolution and refresh rate are too high, in safe mode, remove the monitor, reboot, the problem remains. Finally, the problem is centered on the graphics card. Once again into safe mode, delete the graphics card driver, reboot, skip the graphics card driver installation, can enter the normal boot mode, it seems that the problem is a driver problem or graphics card and other hardware conflicts caused by. Can I download a new driver to see if it solves the problem? Dial-up, the machine suddenly rebooted, is the cat also bad? What should I do? Is the problem really over? The computer won't start up because I took it apart, but the video card and the cat won't break just because I moved the machine, right? When I think about moving the machine, is it possible that the video card was knocked loose when I disassembled the computer, resulting in poor contact and causing a malfunction? Holding the last try, open the chassis, the graphics card and the cat out of the re-insertion of tightly installed, installed the graphics card driver, reboot, surprisingly, see the beautiful desktop, try to dial up, there is no problem, troubleshooting. The original failure is the result of poor contact with the graphics card.
Summary: The above poor contact with the graphics card leads to the computer can not enter the system failure, the phenomenon is somewhat similar to the symptoms of the graphics card failure, if not from the small problems, it is really difficult to solve the problem in a moment, or even suspected of hardware failures, and the big trouble.