What to do if the computer does not boot. Computer won't start
Unfortunately, sometimes you can encounter quite serious problems with turning on computers and starting operating systems, although until a certain point there were no signs of trouble. It happens that most often the computer turns on, but the operating system does not start. It is these situations that will be discussed further. Let's look at questions related to why the computer won't boot and what to do in such situations. There are several universal solutions here.
The computer turns on, but the operating system does not start: reasons
Among all the possible situations when failures occur at the loading stage, several typical cases can be identified.
There are three options:
- a black screen appears;
- Blue screen BSoD occurs;
- The operating system starts, but cannot fully boot.
In the first case, when the computer does not start (the boot does not turn on), messages may appear on a black screen indicating physical or software problems. In the simplest case, when nothing serious happens, the system may report that, for example, the keyboard is missing (for desktop PCs). The simplest solution is to connect it and reboot.
If the computer turns on, but the boot does not start, and instead warnings about software failures or missing files appear on a black screen, there can be many reasons for this system behavior. Among them, first of all, we can highlight problems with the hard drive, damage to the operating system (accidental or intentional deletion of system components or registry entries), exposure to viruses, incorrect boot sector entries, RAM conflicts, etc. By the way, if a blue screen pops up, this mostly applies to the RAM or recently installed device drivers, which cause conflicts not at the software level, but at the physical level.
What to do if the computer does not boot and the operating system does not start for the above reasons? Depending on the situation, there are several solutions. To an uninitiated user, they may seem quite complicated, but in certain situations only they can be used to resuscitate the system. Therefore, you will have to spend both time and effort.
The computer turns on but does not boot: what to do first?
So, let's start with the simplest thing. Let's assume that a short-term technical failure has occurred in the system, for example due to incorrect shutdown or power surges.
As a rule, almost all Windows modifications used today usually automatically activate startup upon restart. If this does not happen, before starting the system you will have to use the F8 key to call up the additional boot menu (Windows 10 uses a different method).
The computer turns on, but the operating system does not start? There's no need to get upset. Here, in the simplest version, you can select the line to load the last working configuration. If everything is in order with the system components, the system will boot without problems. If this does not help, you will have to use the troubleshooting section, and sometimes even trying to boot into safe mode may be successful.
Possible viral infection
Unfortunately, viruses can also cause such situations. What to do if the computer does not turn on? Ways to solve this particular problem boil down to using a powerful one that could check for threats even before the OS itself starts.
Among the variety of anti-virus software, it is worth noting specially disk utilities that start directly from an optical media or USB device, have their own boot records and even a graphical interface like Windows. One of the most powerful tools is Kaspersky Rescue Disk. Its use can guarantee almost one hundred percent detection of viruses, even those hiding in RAM.
RAM conflicts
Now let's see what to do if the computer does not boot and instead a blue screen appears. As already mentioned, most often this indicates problems with drivers and RAM. We’re not touching the drivers yet, but let’s look at the RAM.
The proposed solution to the issue of if the computer does not boot is mainly designed for stationary PCs. In this situation, you should remove all memory sticks, and then insert them one by one and check the load. Perhaps one of them is the link that causes failures. This may occur when trims from different manufacturers are added.
If the system can somehow be loaded using the same safe mode, the RAM should immediately be checked using the Memtest86+ utility, which will help identify the true cause of the problem.
The system does not see the hard drive
Now the worst situation is when the computer does not boot. The causes and solutions may be related to the hard drive.
A hard drive can have both software and physical problems, although sometimes that’s not even the issue. The problem may be completely trivial: the user in the BIOS settings has set the priority for booting from a removable device, for example, from an optical disk, which is currently in the drive, but is not a system one. You just need to remove it and download again.
On the other hand, another problem that the computer does not start (the system does not start) may be due to the fact that the bootloader and the records of the corresponding sector are damaged. The solution to this situation will be discussed a little later. But in the simplest case, you can try to restore disk data using Recovery utilities.
Sometimes changing the settings of the primary BIOS input/output system also helps. Here you need to find the section related to setting up the hard drive, and in the SATA configuration parameters, deactivate the use of AHCI mode.
Finally, the hard drive may also have purely physical damage, and this cannot be done without outside intervention.
Using the installation disc
Many users clearly underestimate the help that the installation or system image can provide in solving problems associated with situations when the computer turns on, but the operating system does not load.
Firstly, almost any kit includes a so-called recovery console, with which you can eliminate many software failures, and secondly, you can use the command line here. This, by the way, is the most effective method. Next it will be clear how this works.
Problems with the BOOTMGR bootloader
It is believed that the most common problem when the computer turns on, but the operating system does not start, is damage to the Windows boot manager (Boot Manager). In this case, the system just writes that there is no system partition (it simply does not see the hard drive).
You can fix this problem by starting from the boot disk and going to the command line in the recovery console, to open which you press the “R” key. Next, you need to first use the check disk command and then fix (restore) boot records.
The whole sequence looks like this:
- chkdsk c: /f /r;
- Bootrec.exe /FixMbr;
- Bootrec.exe /FixBoot.
After entering commands, punctuation marks are not placed, but the enter key is pressed. If for some reason executing these commands does not have a positive effect, you can alternatively use a complete rewrite of the boot sector, which is performed by the Bootrec.exe / RebuildBcd command. If the hard drive is not physically damaged, this should work, as they say, one hundred percent.
You can also use some third-party utilities. The most suitable program seems to be a tool called MbrFix, which is included in the Hiren’s Boot CD. After calling it, for example, for Windows 7, provided that this particular system is installed, and only on one disk (there is no partitioning), the following should be written:
- MbrFix.exe /drive 0 fixmbr /win7.
This will save the user from having to make changes to boot records, and the boot will be restored.
Problems accessing the NTLDR file
When a message appears that a given component is missing from the system, a boot commit is first applied, as in the previous case.
However, if the result is not achieved, you will need to copy the original file to the root of the system partition. For example, if the drive is "C" and the drive is "E", the command would look like this:
- E:\i386> copy ntldr C:\ (after copying, the system will boot without problems).
Damaged or missing HAL.dll file
If the computer turns on, but the operating system does not load in normal mode, the reason may be a damaged component HAL.dll (a corresponding notification may be displayed on the screen).
In this situation, you need to boot the system in safe mode, call the command console and write the following line in it:
- C:\windows\system32\restore\rstrui.exe (then press the Enter key and restart).
Instead of a total
Here is a brief summary of everything that concerns solving the problem of the inability to start the operating system. Naturally, the issues that the cause could be low power, CMOS battery failure, loose cable connections, dust inside the system unit, or other malfunctions were not addressed here. But in software terms, the above methods work flawlessly.
In this article, we will look at situations in which a computer may not turn on or boot. We will also give some tips to solve such problems.
The computer won't turn on
(When you press the power button on the system unit, nothing happens: the lights don’t light up and you can’t hear the noise of running fans)
When the computer does not show any signs of working, the problem is in the hardware.
Solutions.
Step 1. First, check and rule out “inattentive” reasons:
— did you forget to turn on the button on the extension filter;
— whether the power supply toggle switch is turned off (located on the back of the system unit next to the place where the 220V cable is connected;
Step 3. If the problem is not solved, you should stop searching on your own and contact a service center!
The computer turns on but does not boot
(When you press the power button, you can hear the noise of the cooling systems, but the boot does not reach the desktop)
This symptom can be due to either hardware or software problems.
Symptoms of this problem are divided into 3 subspecies:
I. There is no image on the screen - neither the BIOS screen nor the operating system boot screen
Step 3. If the problem persists, try replacing the BIOS battery on the motherboard - type CR2032
Step 4. If the problem persists, contact the service center.
II. There is a BIOS image on the screen, but Windows OS loading is not visible.
Step 1. Turn off computer. Open the system unit and check whether the power cable and SATA cable are connected to the hard drive.
Disconnect and connect them again.
Step 2. Boot from the Windows distribution and perform a system restore.
How to create a bootable flash drive:
How to boot from a flash drive containing a Windows OS distribution:
How to enter Windows OS recovery mode: article will be added later
Step 3. Reinstall the system
Step 4. If the problem persists or periodically recurs even after reinstalling the system, contact a service center.
- Do not place the system unit on the floor or other particularly dusty surfaces. Try to place the unit on a stand or in a special niche on a computer desk.
- Clean the room more often, including wet cleaning. The less dust there is around the computer, the less often you will have to clean the computer from dust.
- Clean the system unit at least once every six months. We recommend that you trust the cleaning of the system unit to specialists. However, if you consider yourself an advanced user, we recommend reading the article on cleaning your computer.
- At least once every 3 years, replace the thermal paste on the central processor, video card and chipsets that have radiators.
- Once every 5 years, we strongly recommend replacing the BIOS battery (type CR2032), even if the computer is working normally. It's better to do this in advance than it will be an unpleasant surprise at the wrong time.
If the monitor's power button blinks but there is no image, the problem is in the VGA (DVI) signal cable or PC video card.
- Check the monitor signal cable (VGA or DVI), the cable may not fit tightly into the socket. Tighten the cable fixing screws. Try this cable on another screen or install another tested cable on the existing one. Some screens have both VGA and DVI inputs; if one does not work, you need to try another, of course, if you have the appropriate connector on your PC video card.
- The problem is with the video card. If the system unit has 2 or more video cards, try moving the VGA or DVI cable to another video card. Move the video card to another slot. Replace the video card with a proven one. Test your video card on another PC.
At this point, 90% of all monitor malfunctions are exhausted, and we move on to PC malfunctions.
Computer won't turn on or won't boot?
Before we begin describing PC malfunctions, we should understand the terminology, since seemingly identical words used to describe a malfunction have different meanings.
So, the machine does not turn on when, after pressing the computer's power button:
- indicator lights do not light up;
- You can’t hear the noise of operating cooling coolers (fans);
- There is no single sound signal from the built-in speaker, which usually accompanies normal PC booting. Please note that a series of several beeps of varying duration (short/long), on the contrary, indicate a computer malfunction.
The PC does not boot when, after pressing the computer's power button:
- indicator lights are constantly on or flashing;
- the noise of operating cooling coolers (fans) is heard;
- there is a single sound signal from the built-in speaker after the PC starts; The operating system (hereinafter referred to as OS) of the computer does not load, black screen, blue screen of death (BSoD).
What to do if the computer beeps?
When you turn on the PC, if the result is positive for errors, the built-in speaker emits one short beep.
If there is a series of beeps when loading (the computer beeps), then the PC has problems.
The correspondence of the number of signals to their duration, system errors are different and differ depending on the BIOS manufacturers.
When you turn on your PC, pay attention to the BIOS developer (information is indicated on the monitor during boot, and can also be found in the instructions for the motherboard).
The most popular BIOS manufacturers are: Asus, Award, AMI, AST, Phoenix, Compaq, DELL.
If the computer does not turn on, you need to follow a number of recommendations below:
- Make sure that the system unit's power supply is turned on. On the back of the system unit there is a power supply button.
- Make sure that the outlet to which the PC is connected is working properly (see the solution to a similar problem for a monitor).
- Make sure the PC power cable is in good condition; there may be a problem with static charge at the ends of the cable or with the cable itself. Pull out the cable and insert it back. Try a different cable (for example, from a monitor).
- Make sure there is no large amount of dust on the computer boards. Try cleaning your computer using a brush and a vacuum cleaner.
- Make sure the computer's power supply is working properly. Measure the voltage at the output of the power supply with a multimeter. Between the black and yellow wires the voltage should be 12V, between the black and red - 5V. Try another power supply of similar power.
- Make sure the PC power button is working properly. If necessary, replace the button.
- Make sure there are no swollen capacitors on the computer motherboard. If there are any, it is necessary to resolder the capacitors.
- BIOS battery problem. Pull out the battery and check the voltage at its contacts, it should be 3V. Deviations to the smaller side lead to unstable PC operation. Try inserting another battery.
- Make sure the hard drive is working properly. Check if all connectors (power/SATA/IDE) are installed properly. When using a PC, incl. and when loading it, if you put your hand on the hard drive, you can feel a slight vibration, if this does not happen, there is a high probability of problems with the hard drive connection cables or its malfunction.
- Make sure that the RAM (hereinafter referred to as RAM) is in good working order. Try inserting the RAM module into a different slot on the motherboard. If there are several modules, you need to remove them, after which you need to try to insert them into the slots one by one and after each attempt try to turn on the PC. Try replacing the RAM module with a tested, working module.
What to do if the computer does not boot?
As a rule, the computer does not boot due to failures in the operating system or problems with the hard drive. To troubleshoot you need to:
Reinstalling Windows 7.
The computer does not turn on - we are looking for a malfunction. PC diagnostics and troubleshooting.
You press the power button, but it doesn’t boot, but the cooler is running, the indicators are blinking, the screen remains black. Computer won't turn on? Looking for a fault
If after turning on the power computer won't boot, this could be due to several reasons.
■ If at the initial boot stage the message Invalid system disk appears on the screen. Replace the disk, and then press any key, check to see if there is a floppy disk inserted into your computer's drive. If the floppy disk is present in the drive, remove it, then press the Reset button on the front panel of the system unit or turn off the computer's power and turn it on again.
■ The computer may not boot If the operating system boot process stops at any stage, press the Reset button on the front panel of the system unit or turn off the computer's power and turn it on again, then press the F8 key at the initial stage of rebooting the system. A menu will appear on the screen in which you should select Safe Mode using the cursor keys in Windows 2000/XP or by successively pressing the 3 and Enter keys in Windows 98/Millennium Edition. After Windows has finished booting into crash protection mode, check the disks. In Windows 98/Millennium Edition, to do this, select Start > Programs > Accessories > System Tools > Check Disk, and then click the Run button in the Disk Checker window that opens. In Windows 2000/XP, open the My Computer window, right-click on the icon of the drive on which Windows is installed (usually the C: drive), and select Properties from the menu that opens. Click the mouse at the top of the window that appears on the screen, go to the Tools tab, click the Run scan button, check the Automatically fix system errors and Reinstall bad sectors checkboxes, and then click the Run button. Most likely, Windows will prompt you to perform a scan the next time you boot the system; agree to this proposal by clicking on the Yes button. Restart your computer.
If the computer does not boot, then after loading the operating system in safe mode (to select this mode, press the F8 key at the initial stage of Windows boot) in Windows Millennium Edition/2000/XP, you can use the System Restore utility. To do this, select Start > Programs > Accessories > System Tools > System Restore for Windows Millennium Edition/2000 or Start > All Programs > Accessories > System Tools > System Restore for Windows XP. In the right part of the System Restore window that opens, set the switch to the Restore the computer to an earlier point in time position (Restore the computer to an earlier state) and click the Next button. On the left side of the next window you will see an image of a calendar, in the table of which the dates on which Windows automatically created a “snapshot” of the system are highlighted in bold - it is to the state of one of these days that you can restore Windows using this program. These “snapshots” are called system restore points. You can switch months in the calendar by clicking on the buttons with the right and left arrows. Having selected the desired month, click on the date when the restore point you need was created. In the field to the right you will see the time it was created and a short text comment. You can scroll through the list of restore points by clicking the right and left arrow buttons above the restore point descriptions. After selecting the desired restore point, click Next. System Restore will show you information about the selected restore point. Click the Next button to begin system recovery. Within a few seconds, the System Restore program reads all the necessary information from the disk, after which the computer will restart. After the resuscitation process is completed, Windows will boot into normal mode with completely restored settings. System Restore doesn't mean that when you restart your computer, you'll lose any documents or emails you've recently prepared, but programs installed after the restore point was created may not run, so you'll need to reinstall them again.
If, when you turn on the computer's power, sound signals are heard from the system unit, consisting of a series of long or short beeps (the image on the monitor screen may disappear in this case), this means a hardware failure has occurred - most likely computer won't boot because some part of the computer has failed. Contact a computer repair specialist.
In fact, if the computer does not turn on, you can determine the reason yourself, without having any skills. In this case, there are not many reasons, and you can determine what has gone wrong in literally 5 minutes. This is exactly what I want to talk about today, how to do independent computer diagnostics.
To avoid filling your head with unnecessary information, use the article navigation and go straight to the section with your symptoms.
The computer does not turn on and beeps
Let me guess, you probably opened the computer to clean it or change components? But, there are times when no one touched the computer, and it itself began to make squeaks when turned on. Be that as it may, the speaker gives a signal that something is connected incorrectly or is out of order.
Your PC can beep in different ways, it can be: short/long beeps, 3-5 beeps, or even continuously. Each of these signals indicates a specific problem, but each BIOS has its own signals. First you need to determine what version of BIOS you have. The easiest way is to remove the PC cover and look at it, look for a chip there with the inscription BIOS, and under it there will be its version (AWARD, Phoenix, AMI, Intel, UEFI).
Now that you know what BIOS you have, remember the number of signals, look at the table below and it will become clear what your problem is.
BIOS Award Signals
| Signal type | |
| 1 continuous signal | Problems with the power supply. |
| 1 repeating long | Problems with RAM. |
| 1 long + 1 short | RAM fault. |
| 1 long + 2 short | Video card error. |
| 1 long + 3 short | Problems with the keyboard. |
| 1 long + 9 short | Error reading data from ROM. |
| 2 short | Minor faults |
| 3 long | |
| Continuous sound | The power supply is faulty. |
AMI BIOS signals
| Signal type | Decoding and what it means |
| 2 short | RAM parity error. |
| 3 short | Error in the first 64 KB of RAM. |
| 4 short | |
| 5 short | CPU failure. |
| 6 short | Keyboard controller error. |
| 7 short | Motherboard failure. |
| 8 short | Video card memory failure. |
| 9 short | BIOS checksum error. |
| 10 short | Cannot write to CMOS. |
| 11 short | RAM error. |
| 1 dl + 1 cor | The computer's power supply is faulty. |
| 1 dl + 2 cor | |
| 1 dl + 3 cor | Video card operation error, RAM malfunction. |
| 1 dl + 4 cor | No video card. |
| 1 dl + 8 cor | The monitor is not connected, or there is a problem with the video card. |
| 3 long | Problems with RAM, test completed with error. |
| 5 cor + 1 dl | There is no RAM. |
| Continuous | Problems with the power supply or PC overheating. |
Phoenix BIOS Signals
| Signal type | Decoding and what it means |
| 1-1-4 | CPU error. |
| 1-1-4 | Cannot write to CMOS. The battery on the motherboard is probably dead. Motherboard failure. |
| 1-1-4 | Invalid BIOS ROM checksum. |
| 1-2-1 | The programmable interrupt timer is faulty. |
| 1-2-2 | DMA controller error. |
| 1-2-3 | DMA controller read or write error. |
| 1-3-1 | Memory regeneration error. |
| 1-3-2 | RAM test does not run. |
| 1-3-3 | The RAM controller is faulty |
| 1-3-4 | The RAM controller is faulty. |
| 1-4-1 | RAM address line error. |
| 1-4-2 | RAM parity error. |
| 3-2-4 | Keyboard initialization error. |
| 3-3-1 | The battery on the motherboard is dead. |
| 3-3-4 | Video card malfunction. |
| 3-4-1 | Video adapter malfunction. |
| 4-2-1 | System timer malfunction. |
| 4-2-2 | CMOS termination error. |
| 4-2-3 | Keyboard controller malfunction. |
| 4-2-4 | CPU error. |
| 4-3-1 | Error in RAM test. |
| 4-3-3 | Timer error |
| 4-3-4 | Error in RTC operation. |
| 4-4-1 | Serial port problem |
| 4-4-2 | Parallel port problem. |
| 4-4-3 | Problems with the coprocessor. |
In my practice, it most often beeps due to RAM. The fix is quite simple: take out the RAM, clean the contacts and firmly insert it into place until the fasteners click. As for the other sounds, there is a lot of information on the Internet for each of these errors that is easy to find. I see no point in describing it, the article is already cumbersome.
The computer won't turn on at all
If you press a button and the computer does not turn on at all, i.e. no emotions, sounds, squeaks, no indicators light up - first check the power supply. If you have changed the outlet, tightly connected the power cable and there is still silence, remove the PC cover and turn it on. If it spins, then scroll down the page, but if nothing happens, we will check for functionality.
How to check the power supply
- Unscrew the power supply from the computer case and disconnect all wires. Remove the power supply from the computer.
- Take a paperclip and break it in half to make a letter U.
- Take the thickest wire harness with the largest hole (that you disconnected from the motherboard) and insert a paperclip to close it black And green the wire:
- Connect the power cable to the power supply and plug it into a power outlet. Important!!! Do not hold the power supply in your hands and make sure that all wires are disconnected from the motherboard. fees.
Now one of two things: the power supply will either hum and work, or there will be silence. If the power supply starts working by shorting the black and green wires, then the problem is in the motherboard; if there is silence, then you need to buy a new power supply.
Self-repair of power supply: you could write about how to restore the power supply, but I’m more than sure that if you could do it, you wouldn’t be reading this. In addition, often after improper repair of the power supply, other components burn out. I strongly recommend buying a new one (it’s not expensive) and saving your computer and your time.
The computer does not turn on, but the system unit fans are working
It’s not a pleasant situation in which almost everything is unclear. This symptom may hide many breakdowns, which will have to be sorted out one by one to understand what exactly happened.
- PSU is faulty. Perhaps it provides tension, but it is not enough. First, open it up, make sure that there are no traces of burnt parts, liquid on the board from capacitors, and check the capacitors so that they are not swollen as in this photo:
If you find them, most likely this is the problem. The power supply works, but not at full capacity and the computer lacks this. To make sure, take a working power supply from someone and install it for yourself to make sure.
- Video card failure. Your computer is running at full capacity i.e. Does it sound the same as before the breakdown? If yes, connect the speakers to the computer, turn it on and wait for the system greeting (OS boot sound). If this happens, you see that the PC is working, but there is simply no image, this means that the video card is faulty.
- BIOS crashed. This happens, it even happened to me. To try to fix it, turn off the computer, remove the cover, take out the battery (the size of 5 kopecks, similar to the battery in a scale) and wait 20 minutes. Then insert it into place and turn on the computer. If it helps, the BIOS has crashed and I would recommend checking for updates for your motherboard. fees.
- The problem is in the components. Almost always in such cases, the speaker tells you what exactly is wrong with the computer, but it is possible that you do not have one or it is not working properly. Disconnect all components one by one until you find the one with the problem.
Start with the video card. If you have an integrated one and an external one, try removing the external one and connecting the monitor directly to the motherboard. If that doesn't help, remove the RAM and then try inserting it into another slot. Disconnect the HDD, if this is the case, the image will appear.
- Checking the motherboard. Do you see a large chip on the board (like a box of matches), perhaps an aluminum radiator is installed on it?
This is a chipset worth checking out. Turn on the computer and hold this chipset with your finger for 3-5 minutes. If it gets very hot, it means the bridge has burned out. I do not recommend soldering it, because the computer will not work for a long time and after a short time the breakdown will recur.
You can also watch the video, it’s quite possible that I missed something, and I haven’t encountered anything at all:
If nothing helps, it is more than likely that your motherboard is burned out. As I said above, there is no need to solder it, because the next breakdown is not far off.
The computer does not turn on the first time
Most likely, you have swollen capacitors somewhere in your power supply or on the motherboard (see example picture above), which is why this is happening. If I'm right and you find them, immediately turn off the computer and resolder them or take the PC to a service center. Until your computer does not turn on the first time, and then the entire motherboard may burn out!
Reason #2 – bad contact. Open the computer, disconnect everything you see and reconnect everything in place, making sure that everything is connected well. It is also advisable to wipe the contacts with alcohol, then wipe them dry and insert them back.
That's all, I hope I helped you, and you figured out your problem without going to the service center.