What's the reason for the computer to reboot automatically?

　First, the software aspect

　　1, virus

The "Shockwave" virus also prompts the system to start automatically after 60 seconds.

Trojan programs remotely control all your computer's activities, including getting your computer restarted.

Remove viruses, trojans, or reload systems.

　　2, System file damage

System files are corrupted, such as the Win2K under the Kernel32.dll,win98 fonts directory of the system runtime basic files are corrupted, the system will not complete initialization at startup and forced to reboot.

　　Workaround: overwrite install or reinstall.

　　3, timing software or planning task software function

If you set up a reboot or load some of your work programs in the program taskbar, the computer will start again when the timing comes. In this case, we can open the "Start" item, check that there are not familiar with their own execution files or other timed work procedures, shielding them and then power-on check. Of course, we can also enter the "Msconfig" command directly in "Run" to select the startup item.

　　Second, the hardware aspect

　　1, the chassis power supply is insufficient, DC output is not pure, dynamic response is slow.

Users or installed companies often do not attach importance to the power supply, the use of low-cost power supply, it is the biggest cause of automatic restart of the system one of the most suspicious.

① power output power is insufficient, when running large 3D games, such as CPU resources larger software, CPU needs high-power power supply, power supply is insufficient and overload causes power protection, stop output. When the power is off, the load is reduced and the power supply starts again. Because the protection/recovery time is very short, so give us the performance is the host automatic restart.

② power supply DC output is not pure, digital circuits require pure DC power supply, when the power supply of the DC output of the harmonic content is too large, it will lead to digital circuit work error, the performance is a recurrent crash or restart.

The ③CPU workload is dynamic, the demand for current is dynamic, and the dynamic response speed is required. Some poor quality power supply dynamic response time is long, will also lead to frequent panic or reboot.

④ Update equipment (high-end graphics/large hard disk/video card), the increase of equipment (burner/hard disk), power beyond the original power of the rated output power, will lead to frequent panic or restart.

　　solution: Now for high-quality high-power computer power.

　　2, bad memory thermal stability, chip damage or set error

Memory problems cause the system to restart the system to restart the probability of relatively large.

① memory thermal Stability is bad, boot can work, when the memory temperature rise to a certain temperature, it can not work properly, resulting in a panic or restart.

② memory chip is slightly damaged, the boot can pass self-test (set up fast start not fully detect memory), you can enter the normal desktop for normal operation, when running some I/O throughput of software (media playback, games, plane/3d drawing) will restart or panic.

　　Workaround: replace the memory.

③ setting the CAS value of the memory too small can also cause memory instability, causing the system to automatically restart. It is generally preferable to use the BIOS default settings and do not change them yourself.

　　3, the CPU temperature is too high or the cache damage

①CPU temperature is too high often can cause protective automatic restart. The reason is too high temperature is due to the chassis, CPU heat dissipation, the cause of poor CPU heat dissipation: heat sink material heat conductivity is low, radiator and CPU interface between the foreign body (many for quality assurance posts), fan speed is low, fan and radiator dust too much and so on. There are P2/P3 motherboard CPU below the temperature probe damage or P4 CPU internal temperature measurement circuit damage, the motherboard on the BIOS bug in a special condition of the temperature is not allowed, CMOS set the CPU protection temperature is too low, etc. will also cause a protective reboot.

②CPU internal secondary cache corruption is a common CPU failure. The degree of light damage, or can be started, you can enter the normal desktop for normal operation, when running some I/O throughput of software (media playback, games, plane/3d drawing) will restart or panic.

　　Workaround: block level two cache (L2) or first-level caching (L1) or replace CPU exclusions in CMOS.

　　4, AGP video card, PCI card (network card, cat) caused by automatic restart

① external card work non-standard or poor quality, triggering AGP/PCI bus reset signal misoperation caused the system to reboot.

② also has the video card, the network card loose causes the system to restart the case.

　　5, the same port, serial, USB interface access to a faulty or incompatible external devices automatically restart

① peripherals are faulty or incompatible, such as the printer's mouth damage, a foot to the ground short-circuit, USB equipment damage to the ground short-circuit, pin definition, signal level is not compatible and so on.

② Hot Plug External equipment, jitter is too large, causing a signal or power supply instantaneous short circuit.

　　6, optical drive internal circuit or chip damage

The optical drive is damaged and most of the performance is not readable disk/engraving. It is also due to internal circuit or chip damage caused the host in the process of a sudden restart. The optical drive itself is poorly designed and fireware with bugs. Also causes a reboot when the disc is read.

　　7, chassis front panel reset switch problem

Chassis front panel Reset key is actually a normally open switch, the reset signal on the motherboard is a 5V level signal, connected to the reset switch. When the switch is closed, 5V level to the ground conduction, signal level down to 0V, triggering system reset reset, reset switch back to the normal position, at this time reset signal back to 5V level. If the reset key is damaged, the switch is always in the closed position, the reset signal is 0V, the system can not be put on the self-test. When the reset switch is less elastic and the button is not easy to bounce, the switch will appear slightly vibrating to close. Which causes the system reset to reboot.

　　Solution: replace the reset switch.

Also the organic box in the reset switch leads short circuit, causing the host to automatically restart.

　　8, motherboard failure

The case of the motherboard causing an automatic reboot is rare. It is usually related to reset circuit fault, socket, socket has virtual welding, poor contact, individual chips, capacitors and other components damage.

　　Third, other reasons

　　1, mains voltage instability

① Computer switching power supply operating voltage range is generally 170v-240v, when the mains voltage is less than 170V, the computer will automatically restart or shutdown.

　　Solution: Add a voltage regulator (not UPS) or 130-260v wide switching power supply.

② computer and air-conditioning, refrigerators and other large power consumption of a strip words, in these electrical start-up, the supply of computer voltage will be greatly affected, often on the performance of the system reboot.

The solution is to separate their power lines.

　　2, strong magnetic interference

Do not underestimate electromagnetic interference, many times our computer crashes and reboots due to interference, both from the internal chassis CPU fans, chassis fans, graphics fans, graphics cards, motherboards, hard disk interference, but also from the external power line, inverter air-conditioning and even large equipment such as automobiles interference. If our host interference performance or poor shielding, there will be a host of accidental restart or frequent crash phenomenon.

　　3, AC power line connection error

Some users to the power line of 0 direct grounding (do not go to the 0 line of Watt-hour meter), resulting in automatic restart, because from the ground to introduce interference signals.

　　4, plug or outlet quality is poor, contact bad.

Power sockets in the use of a period of time, the elasticity of the reed slowly lost, causing the plug and reed contact between the bad, resistance constantly changing, the ups and downs, the system will naturally be very unstable, once the current can not reach the minimum operating system requirements, the computer will restart. solution, the purchase of quality clearance of good sockets.

　　5, accumulated dust too much lead to the motherboard reset line short-circuit caused by automatic restart.

　　Iv. some examples

　　1, CPU two-level cache bad Instance

A compatible machine that was configured a few years ago: k6-2 200MHz CPU, motherboard with Vx-pro chipset, two 16MB 72 line Edo memory, Windows 98 operating system. In the blue sky and white clouds after the automatic restart, Safe mode is also inaccessible, can only enter the MS-DOS mode. I guess because of the memory quality problem caused the computer to restart the possibility of greater, so first replace the same model of memory test, the fault is still. Replacing the power supply still does not solve the problem. Excluded to the last only the motherboard, CPU and video card, after trying the video card is no problem, the lack of can not find the installation of K6-2 200MHZ CPU old motherboard can only be dropped.

It was also suspected that the BIOS setup might be incorrect and that the recovery to the default value did not solve the problem. After a few days, again fiddling with the computer, inadvertently entered the BIOS and CPU Internal cache a set of disable, save exit restart, the system can start! This estimate should be CPU cache has a problem, then the cache set to open and start the computer, and sure enough the system can not start the normal. Because the cache has been shut down dramatically, the performance of the CPU has been significantly reduced, so Windows 98 is much slower to start and run the program than it used to be, and finally a single CPU will solve the problem.

　　2. Example of power failure

I work in the local computer every day to open (because the Internet is more people), 10 days and a half months of shutdown is a common. In such a high intensity of work, the failure rate of hardware equipment is also very high.

Failure phenomenon: Two compatible machines, one CPU for Athlon XP 1700, one CPU for P4 1.7GHz, host Power is the star of the century power supply. When the computer is running at full load for a period of time (when CPU usage is kept at 100%, the hard disk is reading and writing data), it is automatically restarted regularly. One of the 60GB hard disk and a piece of 80GB hard disk, there is a lack of power supply phenomenon.

Fault analysis and processing: Because these two computers are usually used for document editing, Internet and other normal work normally, only a large number of calculations before the problem. began to suspect that the CPU temperature is too high, but the test indicates that the temperature is normal. Check the hard drive found that one of the hard drive appears bad, but in the replacement of the hard disk reload system after the failure is still, it appears that the hard drive bad way is likely to be the computer often abnormal restart caused. The failure disappears after the new power supply has been replaced.

Apart from two old power supplies, it was found that one of the two identical models of electrolytic capacitors (3300μf/10v) had a yellow-brown granular condensate at the top, and a yellowish-brown granular condensate at the top of the two different electrolytic capacitors (1000μf/16v,3300μf/16v) of the other power supply. This is caused by the breakdown of the capacitance by the leaking fluid. After the electronic market to purchase the same type of capacitor replacement, after the test are back to normal. Here is a reminder, do not put the capacitor positive and negative to the opposite! After the analysis found that the author of the Unit power network often due to overhaul or improper use of electricity suddenly power outages, resulting in the capacitance of the accessories are breakdown, a motherboard has been in a sudden blackout after the strike, check found that a few large electrolytic capacitor breakdown leakage, replace the capacitor back to normal.

　　3, the graphics card contact Bad example

Symptom: Friend Computer Configuration for BenQ BenQ 77G display, gigabyte 8IRX motherboard, P4 1.6G CPU, 80G hard drive, xiaoying PA Speed 3000 graphics card, all to the very cloud waterfall inside the cat, the motherboard with AC97 sound card. Because of the decoration of the house, to move the computer, the computer after the connection has been demolished. Later, after picking up the line, the computer can not start up. Computer self-test Normal, after flashing the motherboard logo, the Windows 98 Start screen, then the cursor flashing, everything is normal, but roughly is about to enter the system, the computer suddenly "tick" a sound restart, restart several times is the case.

　　Fault Analysis: The author of this friend is a pure "rookie", the preliminary judgment may be a general wiring problem, it is likely that the mouse and keyboard connected to the cause. First checked the computer wiring, no problem, will be wiring loose it? Connect all the computers again, the fault is still the same. Start to select Safe Mode to enter the system, the operation is normal, after the reboot into the BIOS to see the CPU temperature, in the normal range, the elimination of overheating caused by the CPU reboot. Friends did not install new hardware, so the elimination of power supply caused by the restart phenomenon.

The causes of the failure may be the following four aspects:

One is the software conflict;

Second, the display resolution or refresh rate setting is higher than the rated value;

The third is the video card and other hardware conflicts, or driver problems caused;

Four is the video card failure.

　　Troubleshooting : Ask a friend what happened to the machine before the failure? Friends said the demolition machine has been used very well, no new software installed. No clues, only from the above four possible causes of failure to troubleshoot. After restart, enter Safe mode, run msconfig command, the startup item is not the operating system necessary to remove the items, restart, the fault remains. It does not appear to be caused by software installation. Next to see if the resolution and refresh rate is too high, in safe mode, the monitor will be deleted, reboot, The fault remains. The final question is focused on the graphics card. Once again into Safe mode, remove the graphics driver, reboot, skip the graphics driver installation, can enter the normal boot mode, it appears that the failure is a driver problem or graphics card and other hardware conflicts caused. Download a new driver to see if we can solve this problem? Dial-up Internet, the machine suddenly restarted again, is the cat also broken? What can be done, really mountain poor water again? This computer is because after the demolition is not able to start, the graphics card and the cat is not because of the machine will not be broken? Think of the handling machine, is it because of the disassembly of the computer card to loose contact caused by trouble? Holding the last try the psychological, open the chassis, the video card and the cat pull out again plug tight well, loaded video card driver, restart, unexpectedly see the beautiful desktop, try dialing, there is no problem, troubleshooting. The original failure is the result of poor contact card.

　　Summary: the above graphics card contact bad cause the computer can not enter the system fault, the phenomenon is similar to the symptoms of the graphics card failure, if not from the small problem, it is difficult to solve 1:30, and even suspected hardware failure, and a great deal of trouble.