It often happens that after a long work without failures, the computer completely unexpectedly crashes. At the same time, the manifestations of breakdowns and their causes can be very different. In any case, first of all, the computer should be diagnosed for a malfunction in order to understand which particular element of the PC is responsible for the malfunctions.
PC does not turn on
If after pressing the power button the computer does not react in any way, the most likely problem is the power supply. A simpler case is the failure of the button itself.
Inspection
Do not immediately remove the system unit cover or go to a service center. First, check if the power cable (the one that connects the PSU and the outlet) has come off. You can try just disconnecting it and then reconnecting. Also inspect the surge protector if it is turned on.
It is not uncommon for the switch on the back of the power supply to be set to off. In this case, the solution to the problem will be the easiest.
Connectors
If a quick external inspection does not bring results, further diagnostics of the computer for a malfunction will require more complex actions. Remove the system unit housing cover. Do not forget to disconnect the PC from the network first.
See if any connectors have moved away from the motherboard. It is best to disable them all, wipe with alcohol or cologne. Then you will have to turn 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 at once: contact oxidation; incorrect connection of wires; accidental breaks in the chain.
Button
If the previous steps did not bring results, the computer diagnostics for the malfunction should continue after disconnecting the power button connector. As you can see in the process, it connects to two pins of the motherboard. Lock them with any metal object, such as a paper clip.
If after that the PC turns on, most likely the power button is broken. To temporarily fix the inconvenience caused by this problem, you can simply change the purpose 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 clip earlier. Now to start the PC you will need to click on the reset button on the system unit.
The second possible malfunction with the same symptom is a short circuit in the Reset key. In order to check this diagnosis, you just need to disconnect the wire coming from the reset button, and then try to turn on the computer in the usual way.
Nutrition problems
If the paper clip did not help, the motherboard is probably not getting the necessary power. In this case, the computer diagnostics for a malfunction should continue with checking the ATX and P4 connectors.
ATX is a wide connector with 24 pins. P4 has the shape of a square, and four wires go to it (sometimes their number can reach eight). Just unplug and then plug in the connectors again.
Power Supply
If the previous actions did not lead to a positive result, the BP failed, 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 complete this step is if you have several computers at home. Otherwise, you will have to contact the service center. Buying a new PSU for diagnosing problems is not the best option, because the device may be serviceable, and the problem may appear due to other problems.
Motherboard
After replacing the power supply, the computer does not turn on? We can say that in this case the computer hardware diagnostics is completed, and the motherboard is out of order. It is best to replace it right away, repairing such equipment does not justify itself, since the price of this procedure may be higher than a new device.
Malfunctioning
If problems arise unexpectedly and haphazardly precisely during its operation, the diagnostics of the computer system should begin by updating the most important software. It can include OS, drivers, antivirus. If no protective equipment has been installed, you should install them and then conduct a full scan of your computer for viruses.
RAM
Often, the stability of the PC is violated due to a malfunction of RAM. There are many applications for checking it. However, Memtest86 + is considered the best. Download and use it is absolutely free.
Before testing, you will need to prepare a bootable USB flash drive.
- Download the distribution package of the program. At this step, it is important to choose a USB INSTALLER, not an ISO image.
- After that, 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 terms of the license agreement. Since starting the program is impossible without confirmation, click on the "I Agree" button.
- In the next step, you will need to select the USB drive to which the application data will be copied. Be careful: all information from the USB flash drive can be deleted during installation.
- Now it remains to click on the inscription "Create". Wait until the computer diagnostic program completes the installation, and then click on "Finish"
Now restart your PC and enter the BIOS. To do this, click on the "DEL" button when the computer just starts to turn on. After starting the BIOS setup utility, go to the "Advanced" menu. In it, select "First Boot Device" and switch the parameter to "USB".
Restart your computer again. If all of the previous steps were completed correctly, the computer diagnostic program will load. The memory check should start automatically. It is advisable to monitor the messages on the screen, sometimes before the test you will be prompted to perform the procedure in safe mode. In this case, to start, you need to press the "F1" button.
Memtest86 + performs 11 tests. In this case, after the completion of the last procedure will begin again. If errors in RAM are found, a red area with their description will appear on the monitor screen. In the case when no problems have been identified after a full check, the application will display the message "Press ESC to exit".
If errors are found during the tests, the RAM should be replaced. If there are several RAM slots, diagnostics and computer repair require checking each of them separately. To do this, install them in the system unit one at a time, and after the change, turn on the Memtest86 + utility again. By identifying a failed device, you can continue to use the computer without it, losing some performance, but eliminating crashes.
Cooling system
If problems occur while running demanding applications, it is highly likely that the PC cooling system is not working efficiently. The problem is exacerbated by dust that settles in radiators. As a result, the stream 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 malfunctions will only require the user to install the appropriate application and monitor the sensors.
AIDA64
One of the best utilities for monitoring the temperature of a computer is AIDA64. After starting the program, you will need to select the "Service" item in the top menu, and then - "System Stability Test". A window with graphs will appear on the screen. They will display the temperature of all the main components of the PC.
After clicking on the "Preferences" button, you can independently choose which sensor data will be displayed on the diagrams. Since it is impossible to diagnose a computer for overheating when the computer is in gentle mode, a special test should be run. To check how the PC behaves when using the processor at the maximum level, in the upper left corner, check the boxes next to the words "Stress CPU" and "Stress FPU".
It is advisable not to leave the device during this check and carefully monitor the data that the program provides. Since making computer diagnostics is only half the battle, in addition to identifying problems, you must also not allow them to disable the PC. If critical temperatures are exceeded, you should stop the test and think about replacing the cooling system. It will not be superfluous to blow out the radiators from dust, and then again check the temperature at maximum load.
Game Crashes
If computer errors occur during games or other applications that actively use the graphics system, computer diagnostics can be performed using the FurMark program.
After starting, the settings window will open. It is advisable to select the maximum resolution supported by the monitor, as well as check the box "FullScreen". Now it remains to click on the inscription "Stress Test".
A three-dimensional image will appear on the screen, but you should not watch it. The main focus should be on the chart that appears below. It shows the temperature of the video processor. Upon reaching critical values, press the "ESC" button to complete the benchmark.
Image defects
If the monitor displays incorrect colors during operation, this problem is often solved by simply replacing the cable. Diagnostics and computer repair initially involve checking components. Try tightening the screws securing the plug. If this does not help, you can wipe the contacts with alcohol, and also check that the cable is working on another computer or monitor.
Did the previous actions fail? Update or reinstall the video driver. It will also be useful to test the graphics card for overheating, as described above.
No sound
How to diagnose a computer and detect a malfunction if a sound is lost? Typically, these problems appear after installing a new video card or updating the drivers for the graphics adapter. Almost all of these modern devices come with an HDMI output through which sound can be output. And with the increase in sound reproducing devices, there is a risk of incorrect auto-tuning.
Launch any player and turn on the music in it. Click on the speaker icon in the system tray, and then click on the “Playback devices” label. In the left column of the window that opens, right-click on each device, and indicating the OS that it should be used by default.
If the sound still does not appear, diagnosing your computer at home will require additional steps. Check the wires that connect the speaker system and 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).
If the sound still does not appear in the speakers, try replacing the cable. Is the audio system silent after this procedure? This means that the computer is fully operational, and replacement requires "acoustics."
HDD malfunctions
How to diagnose a computer when the hard disk is not displayed either in Explorer or in the BIOS? Begin by checking the cables. The easiest way is to use a cable from the HDD that works stably. If such a measure did not help, there is a high probability of damage to the drive itself. In this case, further repair attempts 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 drive can be read, but it is not possible to load the OS stopped on it, then the MBR (boot record) was damaged. To resolve this issue, boot from the Windows installation disc. In the menu, click on "Restore Computer", and then - "Repair Bootloader".