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How can I tell the computer hardware failure?

First, let's look at the computer startup process
1, stored in ROM (read-only memory) in the Bootstrap Loader program, and self-diagnostic program moved to the RAM (random access memory) in the.
2, with the Bootstrap Loader operation, stored in the auxiliary memory devices in the operating system files will be sent to RAM.

3, the implementation of the system files Io.sys and Msdos.sys. Then appears on the screen "Starting Windowsn98 ... ..." message.
4, if Config.sys then execute it.
5, the implementation of the system files Command.com files.
6, if Autoexec.bat will execute it.
7, read the Windows initialization file "System.ini" and the "Win.ini", and then reads the registry files.
8, start over, the initial screen appears, run the operating system.
This process, the ROM BIOS on the motherboard is an exception in the monitoring hardware, including hardware failure, wiring situation, the installation of various types of cards. If an error occurs, nothing appears on the screen, start to stop.
This situation is likely to be hardware failures.
Ⅱ, the system boot sequence
1, PC power supply ON - monitors, keyboards, lights flashing on the chassis.
2, test card - a brief screen graphics information.
3, detection of memory - with the toot of the picture and sound appear on the memory capacity of the information.
4, implementation of the BIOS - the BIOS screen appears briefly the information.
5, testing other equipment - other equipment of information emerged (CPU, HDD, MEM ...)。
6, implementation of the OS (operating system) and the initialization file-Starting Windows 98 and so on.
Ⅲ, when it starts to voice opinions on the motherboard, through the voice can determine what kind of error
According to the motherboard form of different sounds that are different.
AMI BIOS:
1 short: Memory Refresh Failure
2 short: Memory Checksum Error
3 Short: Basic memory errors
4 Short: System Clock Error
5 Short: CPU error
6 short: Keyboard error
7 Short: Real-Mode Error
8 Short: Memory error
9 short: ROM BIOS checksum error
1 long 3 short: Memory Error
AWARD BIOS:
1 short: Start a normal
2 short: Non-fatal error
1 long 1 short: Display Error
1 long 2 short: Keyboard error
Other BIOS to be investigated "BIOS error tone," this is no longer detail.


Second, confusing software fault


Must be a clear distinction between hardware failures and software failures, or costs a great deal of effort to move the computer to the computer market, the owner tells you when a software glitch, what would you feel it. In particular the failure to start could also be caused by software failure. Here we take a look at the startup caused by software failure exception.
Ⅰ, CMOS Setup Error
If the CMOS Setup to set the hard disk is not correct, because the computer does not recognize the hard disk, leading to the hard disk can not be used in the operating system (Windows) to start. The screen but you can not start there should check the contents of the CMOS Setup. To correctly identify the hard disk, you can use the CMOS Setup in the "IDE HDD Auto Detection" option.
Ⅱ, system files error
Windows startup need Command.com, Io.sys, Msdos.sys, Drvspace.bin four documents. If these files were destroyed, even if the recognition of the hard disk can not be started. Then you can use the "Sys.com" File to restore these files. With the boot disk, type "Sys c:" can be.
Ⅲ, initialization files error
Windows at boot time to read "Autoexec.bat", "Config.sys", "System.ini", "Win.ini", "User.dat", "System.dat" six documents. However, in reading them the wrong message if it will take place failed to start. These documents are very difficult to restore, so you want to use Windows to re-set the other methods. But this is not a hardware failure, no need to hold the computer to the computer to the market.
Ⅳ, Windows errors in the initial Windows screen appears largely the fault of software failures. Conflicts between programs or driver issues and so on. This problem can be used to read books, and other methods to resolve.


Third, not failures of hardware failure


Though not a failure, but the frequent user assembly is incorrect or jack pine and so on. Then you can open the computer checks your wiring, sockets and other errors. In the newly purchased hard drive, CD-ROM and other EIDE devices should pay attention to the connection in the middle of the device is set to "SlaveE", will be attached to the edge of the device is set to "Master", if set incorrectly, it may not start or Use the appropriate device error occurred.


4, hardware fault detection methods


Let's take a look at the basic test methods for hardware failures. Does not display any images that appear can use the following method to test out the components malfunction.
1, first of all to prepare a table.
2, will pull out the motherboard from the chassis, then pull out all the components on the motherboard, leaving only the CPU and RAM. And then put the motherboard into the table.
3, the regulated power supply connected to the motherboard.
4, will insert the AGP graphics slot. Of course, if you insert a PCI graphics card is a PCI slot. Insert the card when you should pay attention to some entirely gold-plated plug slot.
5, connect the power jack will display graphics and displays connected.
6, open the display power, and then connected to the chassis power switch. Then use the rod contact with the motherboard power switch.
Motherboard power switch is connected with the chassis part of the power switch, generally labeled "PWR SW" or "POWER SE".
7, if the screen version of the BIOS information appears on screen is not unusual, then shows CPU, motherboard, RAM, graphics card, power supply are normal. In general, frequent failures of the components are easy to "graphics", "Motherboard", "hard drive" is sequence.
8, and then connect the hard disk and soft zones for testing. Then connect CD-ROM detection, and then the sound card. Modem connection such as one by one for testing. If you do not appear on the screen that shows the connection after the faulty parts or have compatibility issues. Only to deal with that component failure can be.
9, chassis problems
Sometimes the motherboard to the chassis when a problem occurs, resulting in failed to start. Therefore, if the components in the above examination without any problem, install the motherboard into the chassis can be tested. If the test without any errors, then the description is CMOS Setup error, the driver and other software issues.

A simple method of detection of computer failure


If you exclude the "false failure", then the fault is really in existence! Ruozai detect the appearance of what the various parts, including the open the case to see the components inside the surface of the host are not destroyed by high-voltage signs, or obvious signs of injury, if any, fault components to clear. If not, can first try the following approach.
1. Remove dust
The dust floating in the air is a major killer of a computer, use a period after the main board and other key components may be due to dust accumulation too many failures, even in the private room in the case. Therefore, the use of a computer for a long time, they should first be cleaned with a brush to gently brush the motherboard, peripherals on the dust. If the dust has been cleaned out, or no dust, fault still exists, it shows that there is another hardware problem.
In addition, because some card board or chip pins form, vibration, dust and other reasons they often have a pin-oxidation, poor contact. Eraser Wipe the surface oxide layer can be used to re-start after a good plug check to verify the fix.
A casual remark, the keyboard tends to occur after prolonged use, leakage, such as buttons stuck fault, this fault should be a timely manner, or else the input file will be typed some wrong characters. And should be approached with a bracket to prop the keyboard up and down keys, open the rear cover the keyboard, using alcohol to clean circuit boards and key contacts, and to get stuck buttons below the appropriate Lever shrapnel, making restoration of the original Some flexibility.
Note: The floppy disk in use, dirty or scratch the floppy disk into floppy drive read-write head will be scratched, damaged floppy. Washing must be very careful when you head for a long time without a floppy drive, may be rust on the head, this time not use cleaning disk, the specific practice is to open the case to drop the head on the cleaner, soaking half an hour later, with fat cotton carefully wipe clean. If you blindly use of clean floppy disk read-write head is bound to lead to injury, so floppy scrapped.
2. To see, hear, smell, touch
"See" that the observation system board plugs, sockets whether the skew, resistance, capacitance pin is touching the surface, whether there are scorch marks, the chip surface is cracking, copper on the motherboard is blown. Of course, needless to say you know but also to see if there is foreign matter between the components fall into the motherboard (which will result in short-circuit), may also look at whether there are charred color board where the alignment of printed circuit board ( copper) whether it is broken and so on.
"Listen," that is to listen to power fans, soft / hard disk motors or seek agency, monitors the work of transformers and other equipment, the sound is normal. In addition, the system often accompanied by a short circuit fault from time to time with the unusual sound, listen to can be found in a number of potential accidents in a timely manner prior to the incident and immediate action.
"Smell" that is identified Wen host board if there are burnt smell, easy to find fault and determine the short-circuit location.
"Touch" that the activities of hand-press tube socket chip, chip to see whether loose or poor contact. In addition, the system is running their hands touching or near the CPU, monitor, hard disk enclosure and other equipment can be judged according to their equipment running temperature is normal; hand touching the surface of some chips, if hot, compared to the chip is damaged.
3. Pluggable test
As mentioned above, computer-generated are many reasons for failure, motherboards own fault, I / O bus failure, a variety of card failure can cause the system not functioning correctly. Using plug repair method is to determine the failure occurred in the motherboard or I / O devices fast-track approach. The method is to shut down, it will pull out the plug-in board-by-block, each pulled out a sheet on the observation of the machine start running, once pulled out a piece of board, after operating normally, then the cause of the malfunction is that the plug-in board failure or the corresponding I / O Bus slot and the load circuit fault. If the pull all the plug-in board to start after the system is still not normal, then the fault is likely on the motherboard.
Plug detection, but also to exclude from the other side of computer failures: A number of chips, boards and slot connection is bad, will these chips, boards pull out right after the re-insertion can be solved by the installation of improper exposure due to computer component failure .
4. Switch Detection
Will be the same type plug-in board, consistent with the way the bus, feature the same plug-in board or the same model chip exchange, according to the evolution of failure phenomena can also be judged failures. This method is used for easy plug maintenance environment, such as memory, self-test error, the same interchangeable memory chips or memory to determine the fault location, fault-free chips are exchanged between the fault phenomenon remains the same, if the exchange after the failure phenomenon of change, is illustrated in the exchange of chips there is a bad, could be further determined by the exchange-by-block site. If we can find the same type of computer components or peripherals, use the exchange method can quickly determine whether it is the quality of its own components.
5. Comparison of detection
Run two or more or less the same or a type of computer, according to the normal computers and computer failures in the implementation of the different manifestations of the same operation can be generated initially to determine the site of failure.
6. Vibration tapping test
Chassis with your fingers gently tapping shell, if troubleshooting, and note the failure was caused by a poor contact or a cold solder joint. You can then further examine the location of the point of failure and to exclude only such failure is difficult to detect the exact location.
7. Heating cooling detection
Artificially increase the temperature of computer operating environment, you can test the components, especially the CPU's temperature, resulting in early detection of accidents. Reduce the operating temperature of the environment, if the rate of failure appears greatly reduced, indicating fault lies in the high temperature or high temperature components can not be in a move that could help narrow the scope of fault diagnosis.
In fact, the heating temperature used is the stimulation of the fault principle in order to create the conditions for failure to induce failures occur frequently in order to observe and judge the location of faults, but pay attention to controlling the specific implementation, a good heating method, the temperature must not exceed 40 degrees Celsius.
8. Run the detection program
With the extensive application of a variety of integrated circuits, the welding process more complex, the general maintenance of the means alone is often difficult to identify the fault lies, but through random diagnostic procedures, special maintenance diagnostics card and based on various technical parameters (such as the interface address), self-compiled program to support specific diagnostic testing, often have a multiplier effect. Program to test the principle is to use the software to send data, commands, through reading the line status, and a chip (such as the register) state to identify the fault position. This method is often used to examine the various interfaces with the address parameter circuit fault and a variety of circuits, but the application of the premise that the basic CPU and bus operating normally, be able to run the diagnostic software that can run the installation on the I / O bus slots on the diagnostic cards.
Choice diagnostic procedure to be strict, comprehensive, targeted, allowing emergence of certain key parts of a regular signal, able to carry out repeated tests occasional failures, and can display error log.

How to diagnose computer failure


Many beginners new to the computer share a fear that the computer failure necessarily insurmountable ones. In fact, the majority of computer failures have certain rules to follow, this problem is like a layer of the windows of paper, a barrel on the break does not require you to have too much computer knowledge. Let us learn together the following recipe for a quick way to diagnose computer failures.
Environmental Inspection Act
For some sudden hardware failure, such as the boot no display and so on. We should not conduct in-depth consideration, since it is often we will overlook some of the details. First, we should look at the obvious things: If not connected to the power supply? Switch is turned on? Power outlet there is no electricity? Is not all of the wiring are connected to it? Perhaps the root of the problem on one of them.
CMOS reduction
Some users tend to change because of curiosity, where some of the motherboard CMOS settings, and this is precisely one of the main reasons leading to failure occurred. If the computer failures can be attributed to, then we can restore the CMOS settings to resolve the problem. Method is very simple, turn on the keyboard, press the "Delete" key to enter the motherboard CMOS, choose the "Load Optimized Defaults" (loading the default setting), press "Y" button to confirm, Save and Exit CMOS can be.
Registry Restoration Act
Some users like to modify the registry to achieve the optimization of the system settings or personalized settings, and some users when browsing a malicious program changes to the registry, a number of failures because of the registry is not caused by normal changes. Then we can restart the computer, and switch to MS-DOS mode, type in C under the root directory and execute "scanreg / restore" to restore access to the registry interface, and then select a computer registry files when the good conduct " Restore (restore) ", can be realized on the registry recovery.
Streamline the startup method
Part of the computer failure was after we installed some software, and if this time the computer can also enter the operating system, then we can in the Start menu, run "msconfig" program, turn off the startup menu except "internat.exe, Scanregistry, Systemtray "outside of all programs. If, after you restart your computer problem no longer occurs, then the problem is mostly a result of self-starting software.
logged tracing method
If the computer has been unable to enter into the Windows or entering the latter is not normal, then we can use Logged (\ Bootlog.txt) the way you start your computer, so that files can be generated record Bootlog.txt failure to appear. Logged ways to use the method of activation is at boot time by pressing the F8 key on the keyboard, there will be boot menu, choose to be activated Logged fault appears, with the Windows boot disk to restart the computer, and then under the root directory C The Bootlog.txt file to a floppy disk, on other computers to open the file, you will find the above record of the entire Windows startup process, from which you can find the source of the problem.
Equipment substitution
The so-called replacement of equipment, which device is that when you suspect there is a problem with the same function (preferably the same type) equipment to replace it, if the problem goes away after the replacement, then that is probably a problem with this device.
Minimum System Act
If you can not determine which hardware problems, you can use to determine the minimum system method. Minimum System law is to remove the system to other hardware devices, leaving only the motherboard, memory, video card three basic components, and then observe whether there are boot failure. If so, can the exclusion of other hardware problems, failure should come from the three existing hardware. If not, will add 11 other hardware to see what you add after the failure of hardware, and found that after the fault lies, and then processed for the hardware can be.
Upgrade Procedure Act
Many people not paying sufficient attention to the driver that just having one on it. However, we already have in the purchase of hardware drivers, why the hardware manufacturers should constantly release new version of the driver procedures? In fact, the purpose of doing so is to enable manufacturers to their products more perfect.
Now that the hardware updates very fast, and most hardware manufacturers to software before the hardware R & D research and development, thus supporting the hardware drivers for the just-released when there may be some small Bug, needs to constantly update the driver to compensate for these deficiencies . Therefore, upgrade the driver for solving an effective method of hardware failure.
Software Test
Diagnosis of hardware failure usually need to know some of the hardware aspects of information, but many people do not record information on custom hardware, or do not know how to record. A computer failure, it may not be able to enter the system at this time we need a DOS to test the hardware tools, such as HwInfo for DOS, its size is only 582KB, on a floppy disk where I can carry it at any time by means of Diagnosis of hardware failure.
Change Resources Act
Many computer problems are by hardware resource conflicts between the cause, and which we can use to change the way of resources to resolve. Right-click on "My Computer" in the drop-down menu, select "Properties" one, click on "Device Manager", select "View devices by type" in the list if the equipment was found to have a yellow exclamation mark, it is likely to be made between the hardware resource conflicts. To change the resources approach is marked with the left mouse button double-click the exclamation point of the hardware, select "Resources" one to remove the "Use automatic settings" hook before the election, select "Change Settings" to change the resources of the conflict can be .

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