Often it happens that after a long work without failures, the computer completely unexpectedly fails. In this case, the manifestations of breakdowns and their causes can be very different. In either case, the computer must first be diagnosed with a fault in order to understand which element of the PC is responsible for the malfunction.
The PC does not turn on
If the computer does not react after pressing the power button, the most likely problem is the power supply. A simpler case is the failure of the button itself.
Do not immediately remove the cover of the system unit or go to the service center. First, check if the power cord (the one that connects the power supply unit and the power outlet) has gone. You can try to just turn it off, and then reconnect it. Also, inspect the mains filter to see if it is on.
It is not a rare situation when the switch on the back of the power supply is set to "Off." In this case, the solution to the problem will be the simplest.
If a cursory external examination does not bring results, further computer diagnostics for a malfunction will require more complex actions. Remove the computer cover. Do not forget to disconnect the PC from the network.
Look to see if any connectors have left the motherboard. It is best to turn them all off, wipe with alcohol or cologne. Then you'll have to refer to the manual that comes with the motherboard. It will indicate where to connect all the wires.
With this approach, several possible causes of the malfunction can be eliminated: the oxidation of contacts; Incorrect wiring; Random discontinuities in the chain.
If the previous actions did not work, the computer should be diagnosed with a fault after disconnecting the connector of the power button. As it was possible to notice in the course of work, it is connected to two contacts of the motherboard. Close them with any metal object, for example, with a paper clip.
If after that the PC turned on, the power button is likely to be broken. To temporarily eliminate the inconvenience caused by this problem, you can simply change the assignment of the "Reset" key by connecting its wire to the "Power On" connector on the motherboard. That is to the one that was closed with a paper clip earlier. Now, to start the PC, you will need to press the reset button on the system unit.
The second possible malfunction with the same symptom is the short-circuit of the "Reset" key. In order to check this diagnosis, you should simply disconnect the wire from the reset button, and then try to turn on the computer in the usual way.
If the clerical clip did not help, it is likely that the motherboard does not receive the necessary power. In this case, the computer should be diagnosed to be faulty by checking the ATX and P4 connectors.
ATX is a wide connector with 24 contacts. P4 has the shape of a square, and four wires lead to it (sometimes their number can reach eight). Just unplug and then reconnect the connectors again.
If the previous actions did not lead to a positive result, the BP went out of action, but so far the probability of this is not 100%. Further computer diagnostics at home will require the connection of a known good power supply to the PC.
The easiest way to do this is if you have more than one computer at home. Otherwise, you need to contact the service center. Buying a new BP to diagnose problems is not the best option, because the device can be serviceable, and the problem can be manifested due to other problems.
After replacing the power supply, the computer does not turn on? We can say that in this case, the diagnosis of computer hardware is completed, and the motherboard is out of order. It is best to replace it immediately, the repair of such equipment does not justify itself, since the price of this procedure may be higher than the new device.
Failures in operation
If problems occur unexpectedly and systematically during its operation, the computer system diagnostics should begin with the update of the most important software. It can include OS, driver, antivirus. If no security features are installed, it is worthwhile to install them, and then perform a full scan of the computer for viruses.
Often, the stability of the PC is broken due to a malfunction of the RAM. To test it, there are many applications. However, the best is Memtest86 +. Download and use it can be absolutely free.
Before testing, you need to prepare a bootable USB flash drive.
- Download the distribution kit. In this step, it is important to select the USB INSTALLER, not the ISO image.
- Then run the executable file. Its extension is EXE, and the name begins with "Memtest".
- A window will appear on the screen that asks if you agree with the items in the license agreement. Since you can not start the program without confirmation, you should click on the "I Agree" button.
- The next step is to select the USB drive to which the application data will be copied. Be careful: all information from the USB flash drive can be removed during the installation process.
- Now it remains to click on the inscription "Create". Wait until the computer diagnostic utility finishes the installation, and then click on "Finish"
Now reboot the PC and enter the BIOS. To do this, press the "DEL" button when the computer just starts to turn on. After running the BIOS setup utility, go to the "Advanced" menu. In it, select "First Boot Device" and switch the parameter to "USB".
Restart the computer again. If all the previous items were executed correctly, the program for diagnosing the computer will boot. The RAM test should start automatically. It is advisable to follow the messages on the screen, sometimes before the test will be asked to perform the procedure in safe mode. In this case, you need to press the "F1" button to start.
Memtest86 + performs 11 tests. At the same time, after the completion of the last procedure will begin from the beginning. If errors in RAM are found, a red area with their description will appear on the monitor screen. In case when after a full check of the problems is not revealed, the application will display the message "Press ESC to exit".
If errors are found during the tests, the RAM should be replaced. If the RAM slots are multiple, the diagnosis and repair of computers involves checking each of them separately. To do this, you need to install them in the system block in turn, and after the change again, use the utility Memtest86 +. Having determined the faulty device, you can continue to use the computer without it, losing a bit of performance, but eliminating failures.
If problems occur during the operation of resource-intensive applications, the chances are that the cooling system of the PC is not working efficiently. The problem is aggravated by the dust that settles in the radiators. As a consequence, the flow of cool air, pumped by the fan, becomes unable to blow all the metal parts of the heat exchanger.
To detect overheating, a program can be used. Diagnosing a computer for a malfunction will require the user to install the appropriate application and monitor the sensors.
One of the best tools for monitoring the temperature of the computer is AIDA64. After starting the program, you need to select "Tools" in the top menu, and then "System stability test". A window with graphs appears on the screen. They will display the temperature of all the main components of the PC.
After clicking on the "Preferences" button, you can choose which data will be displayed on the diagrams. Since it is impossible to diagnose a computer for overheating, when the computer is running in sparing mode, you should run a special test. To check how the PC behaves when using the processor at the maximum level, in the upper left corner, check the box next to "Stress CPU" and "Stress FPU".
It is advisable not to depart from the device during this check and closely monitor the data provided by the program. Since it is only half the case to make computer diagnostics, in addition to troubleshooting, you should also not allow them to disable the PC. If the critical temperatures are exceeded, stop the test and think about replacing the cooling system. It is not superfluous to purge the radiators from dust, and then again check the temperature at maximum load.
Crashes during games
If computer errors occur during games or other applications that are actively using the graphics system, computer operation diagnostics can be performed using the FurMark program.
After the startup, the settings window opens. It is desirable to select the maximum resolution supported by the monitor, and also tick the "FullScreen" checkbox. Now it remains to click on the inscription "Stress Test".
A three-dimensional image appears on the screen, but it should not be followed. The main attention should be focused on the schedule, which will be displayed below. It shows the temperature of the video processor. When critical values are reached, click on the "ESC" button to exit the benchmark.
If incorrect colors are displayed on the monitor during operation, this problem is often solved by simply replacing the cable. Diagnosis and repair of computers initially involve testing the components. Try to tighten the screws securing the plug. If this does not work, you can wipe the contacts with alcohol, and also check the performance of the cable on another computer or monitor.
The previous actions did not lead to success? Update or reinstall the video driver. Also, it will not be superfluous to test the graphics card for overheating, as described above.
How can I diagnose a computer and detect a malfunction if the sound disappeared? Typically, these problems occur after installing a new video card or updating the graphics driver . Almost all such modern devices come with an HDMI output, through which sound can be output. And along with the increase in sound-reproducing devices, there is a risk of incorrect autotune.
Start any player and turn on the music in it. Click the speaker icon in the system tray, and then click on the "Playback Devices". In the left column of the window that opens, right-click each device, and tell the OS that you want to use it by default.
If the sound does not appear, computer diagnostics at home will require additional actions. Check the wires that connect the speaker system and the audio output. The easiest way to do this is by disconnecting the plug from the computer connector and connecting it to any other audio device (TV, portable player, mobile phone).
In the event that the sound in the speakers still does not appear, try replacing the cable. Is the audio system silent after this procedure? Hence, the computer is fully functional, and replacement requires "acoustics."
How to diagnose a computer when the hard disk is not displayed in the explorer, or in the BIOS? You should start by checking the cables. The easiest way is to use a cable from the HDD, which stably works. If such a measure does not help, the probability of damage to the drive itself is high. In this case, further attempts at repair at home will not lead to positive results. Data recovery from this HDD can only be performed by a specialist.
If the information from the hard disk can be read, but the OS stopped on it does not work, then the MBR (boot record) has been corrupted. To resolve this issue, boot from the Windows installation disk. In the menu, click on "Restore computer", and then - "Restore bootloader."