Bios signals three long, 1 short. BIOS signals from Award. The most common BIOS beeps

American Megatrends, Inc. (AMI)

The checkpoints of the POST procedures performed in AMIBIOS were redesigned and supplemented in 1995 and have not undergone significant changes to date. The first description of POST codes or as AMI calls them - "check points" in their current form appeared in connection with the release of the V6.24 kernel, 07/15/95. Some changes have been made to AMIBIOS V7.0, which are reflected in this document.

Features of performing AMIBIOS startup procedures

If during the startup process the data 55h, AAh appears in the diagnostic port, you should not compare this information with POST codes - we are dealing with a typical test sequence, the task of which is to check the integrity of the data bus.

At the start stage, the output to the diagnostic port of data is specific to each platform. In some implementations, the first code rendered is associated with actions, which AMI calls chipset specific stuff. This procedure is accompanied by outputting the CCh value to port 80h and performing a number of steps to configure the registers system logic. As a rule, the CCh code appears in cases where system logic from Intel is used, built on the basis of the PIIX controller - these are TX, LX, BX chipsets.

Some on-board I/O chips contain an RTC and a keyboard controller, which are disabled at startup. The purpose of the BIOS is to initialize these board resources for further use. In this case, the first startup procedure associated with setting up the keyboard controller is accompanied by the output of the value 10h, then the RTC is initialized, as evidenced by the appearance of the DDh code in the diagnostic port. It should be noted that the failure of at least one of these resources will result in a non-start of the system board as a whole at the very first stage of POST execution.

On a number of boards, the initialization process begins with the CPU switching to protected mode. In this case, following the first rendered code 43h, the POST execution continues as described in the AMIBIOS documentation - control is transferred to point D0h.

Unpacked initialization procedure codes

Uncompressed Init Code Check Points

Flash ROM rewrite procedure codes

Boot Block Recovery Codes

Unpacked system BIOS codes executed in ShadowRAM

Runtime code is uncompressed in F000 shadow RAM

Features of the Device Initialization Manager

In addition to the above POST codes, messages about events during the execution of Device Initialization Manager (DIM) are output to the diagnostic port. There are several control points that indicate the initialization status of system or local buses.

The information is displayed in word format, the low byte of which coincides with the system POST code, and the high byte indicates the type of initialization procedure being performed. The most significant tetrad in the high byte indicates the type of procedure being executed, and the low tetrad determines the bus topology for its application.

Senior tetrad

Junior tetrad

If a system memory configuration error is detected, the DE code, DF code, and configuration error code are output to port 80h sequentially in an endless loop, which can take the following values:

2. Award BIOS V4.51PG Elite

AwardBIOS V4.51PG Elite

The dynamically developing company Award Software in 1995 proposed a new solution in the field of low-level software- AwardBIOS "Elite", better known as V4.50PG. The control point maintenance mode has not changed either in the widespread version V4.51 or in the rare version V4.60. The suffixes P and G denote support for the PnP mechanism and support for energy saving functions (Green Function), respectively.

Performing a POST in Shadow RAM

3. Award BIOS V6.0 Medallion

AwardBIOS V6.0 Medallion

The first mention of Award Medallion BIOS, Version 6.0 dates back to May 12, 1999. The structure of the new product remains unchanged, retaining the early (Early), late (Late) and final (System) phases of hardware initialization. Significant changes affected the POST execution algorithms, which was reflected in the new encoding of checkpoints, significantly expanding their scope of application. However, in the new BIOS there was no place for outdated technologies such as EISA, and for this reason a number of POST codes were abolished.

Executing startup POST procedures from ROM

At the early initialization stage program code BIOS is executed from the Boot Block in Flash ROM, and is accompanied by the output of control points 91h...FFh to the diagnostic port

BIOS recovery

Performing a POST in Shadow RAM

Late initialization is performed in RAM and continues until the user menu is called - CMOS Setup. This POST phase is characterized by the use of memory segment E000h, in which the passage of checkpoints from 01h to 7Fh is processed.

Preparing tables, arrays and structures for starting the operating system

Starting with code 82h, POST configures the system according to the CMOS settings. Its final phase is executed from the Shadow RAM area (segment E800h) and ends with the transfer of control to the operating system - code FFh.

A number of processes occurring in the Award Medallion BIOS are designated by special groups of control points. These include:

System Event codes - control points system events.

Power Management Debug codes are checkpoints that occur during the execution of APM or ACPI services.

System Error codes - messages about fatal errors.

Debug codes for MP system - initialization points for multiprocessor platforms.

Features of accelerated POST passage

To reduce system boot time, the user in CMOS Setup can select the option " Quick Power On Self Test". In this case, the POST will be accelerated by refusing to perform some procedures (Quick Boot).

The Quick Boot operating pattern replaces the late and final POST phases and does not affect the operation of the boot block. Award Software offers a codification of the executable expedited POST procedures that differs from the standard one. Quick Boot begins with the output of checkpoint 65h to the diagnostic port and ends with POST code 80h. Control is then transferred to the operating system, displaying the usual Award BIOS code FFh.

Performing a POST in Power Saving Mode

One of the platform states, when the contents of RAM are stored on the hard disk, is called Hibernate. In the ACPI specification ("Advanced Configuration and Power Interface Specification", Revision 2.0a dated 03/31/2002) it is defined as the S4 (Non-Volatile Sleep) power saving mode. Returning to full functioning requires a special way of completing POST.

The ACPI S4 operating scheme, as with the accelerated start, replaces the late and final phases of POST. An essential point is checking the startup script in the boot block. Depending on what ACPI state the system is in after the hardware Reset signal, a decision is made to exit state S4, which begins with the output of test point 90h to the diagnostic port and ends with POST code 9Fh.

4. Phoenix BIOS 4.0 Release 6.0

Phoenix Technologies, Ltd.

One of the leaders in low-level software development, Phoenix Technologies, has released a new version of PhoenixBIOS 4.0 to coincide with the release of Windows95. Support for the Intel Pentium processor family is reflected in the names of the intermediate revisions. One of the latest - Release 6.0 - formed the basis for all released BIOS. With the advent of Release 6.1, there were no significant changes in the execution of POST procedures, and, therefore, this did not affect the indication of checkpoints.

A distinctive feature of PhoenixBIOS is that if during the POST execution errors occur when testing 512 KB of main memory (codes 2Ch, 2Eh, 30h), additional information is output to port 80h in word format, the bits of which identify the failed address line or data cell. For example, the code "2C 0002" means that a memory fault has been detected on address line 1. The code "2E 1020" in this case will mean that a fault has been detected on data lines 12 and 5 in the low byte of the memory data bus. On 386SX systems that use a sixteen-bit data bus, an error cannot occur during code execution step 30h

The POST code output to the diagnostic port is accompanied by an audio signal output to the system speaker. The sound signal generation scheme is as follows:

• The eight-bit code is converted into four two-bit groups
• The value of each group increases by one
• Based on the received value, a short sound signal is generated (for example: code 16h = 00 01 01 10 = 1-2-2-3)

Executing startup POST procedures from ROM

Fatal Error Messages

D0 Error caused by an exceptional situation (Exception error) D2 Calling an interrupt handling procedure from an unidentified source D4 Error associated with a violation of the protocol for issuing and clearing interrupt requests D6 Exiting protected mode with software reset generation D7 To save the state of the video adapter, more is required amount of memory than is available in SMRAM D8 Error during software generation of the processor reset pulse DA Loss of control when returning to Real Mode DC Exit from protected mode with software reset generation without re-initializing the interrupt controller DD Error when testing extended memory DE Keyboard controller error DF Line control error A20 19

Executing Procedures from Boot Block

5. Insyde BIOS Mobile Pro

Insyde Software Corp.

Market Insider mobile systems has firmly established itself where loyalty to tradition and a conservative approach to building a BIOS are required. Having inherited the source code from SystemSoft, the company is constantly working to improve it. The latest revision of MobilePRO is actively used in Mitac and Clevo laptops, the documentation for which formed the basis of the Error Codes table - this is what Insyde Software calls POST checkpoints.

Boot block checkpoints

Despite the fact that Insyde Software created its first BIOS in 1992, the established model of the boot block - or Boot Loader, as the creators themselves called it - was finally formed only by the end of 1995. From this moment on, the starting procedure was numbered by version and creation date.

The most significant point from the point of view of a service engineer examining the process of booting a computer system with InsydeBIOS is the diagnostic code display device. Although, as a rule, Boot Loader uses Manufacture's Diagnostic Port 80h, standard in such cases, in some cases, test point output is performed only on the PIO Port (Parallel Input/Output port for diagnostic purpose), which is nothing more than a parallel port 378h There are implementations in which diagnostic codes sent to port 80h are duplicated to the parallel port.

Executing POSTs from RAM

The most modern solutions InsydeBIOS use 16-bit checkpoint mapping. This is done using ports 80h and 81h, the latter of which is intended to extend standard diagnostics.

The study of control points is made difficult by their irregular construction, when processes of different meaning are accompanied by the same codes. In dual diagnostic systems, there are differences of a different order: some POST codes are displayed only in one of the ports without the usual duplication in such cases.

Hearing a BIOS signal (1 long beep), the user usually becomes wary. After all, as you know, in most BIOSes the message about the successful completion of hardware testing sounds somewhat different, although it is similar - one signal, but a short one. Is there any cause for concern in this case? Practice shows that in most cases - Yes.

First of all, it is worth defining the concept of “long signal”. In many cases, one continuous sound can be considered long. If you hear a similar sound and you have an Award BIOS installed, then this means that the power supply is faulty. When Phoenix BIOS In such a situation, there is a malfunction of the CPU cooler fan. In the Compaq BIOS, this type of sound indicates a problem with the RAM.

However, most often the user may encounter a slightly different situation, when there is only a long but time-limited signal. This type of signal is used by many BIOS manufacturers to encode error messages.

However, one long BIOS beep is a sound that is often used for more than just signaling errors. For example, you can find BIOS version famous manufacturer American Megatrends, in which the BIOS signal 1 long beep is used to notify about the normal completion of tests instead of the usually used short beep. A similar approach is also used in the Mylex 386 BIOS. This factor should also be kept in mind, especially if you are dealing with specific computer for the first time.

In AST BIOS, one long squeak has a completely different meaning, namely, an error detected when testing the first channel of the DMA controller. Typically, this situation means the microcontroller is faulty, which may result in the need to replace the entire motherboard.

In IBM BIOS, a similar BIOS signal, one long beep, also has its own meaning - this is a malfunction of the video system. You can try to fix this problematic situation yourself by checking that the video card is securely installed in the motherboard expansion slot.

A fairly common situation is the problem when, when turning on the computer, the user hears one long and two short BIOS beeps from the system speaker. In this case, the operating system does not load at all, and the user sees a black screen in front of him (sometimes messages indicating a problem may appear, but, as a rule, they are absent). Read on to learn how to interpret this sequence of signals and what to do to correct the situation.

One long, two short BIOS beeps: what does this mean?

Let's start with theoretical information. When you turn on your desktop computer or laptop, all hardware is checked. The primary one is responsible for this. BIOS system(or its modernized version UEFI). For each such system, the use of strictly certain sequences signals that may indicate either that the test was completed successfully, or that problems were found in the operation or initialization of the equipment. In general, to figure out what the problem is, you need to contact technical documentation primary system or at least read what different sequences and combinations mean.

In general, if the user hears one long and two short beeps from the BIOS of ASUS or any other developer of the primary system, we can immediately conclude that something is wrong with the installed hardware. Unfortunately, the system does not provide notifications about faulty components.

The only situation is a message about the absence of a connected keyboard. But this mostly applies exclusively to stationary terminals, since on laptops such a message can only appear if the built-in keyboard has become unusable. Connect any other external keyboard, for example, via USB and check how the system boots.

One long, two short BIOS beeps: what to do first?

The issuance of such a sequence of signals may not always be associated specifically with physical damage installed equipment. It is quite possible that somewhere on the motherboard the contacts have simply come loose or become clogged. All components may be in perfect order, but dust or contamination of the inside of the computer can lead to the fact that some elements of the filling are simply not detected.

In the simplest case, if you receive one long and two short signals from the BIOS, you should immediately turn off the computer and completely disconnect it from the power supply. After this, you need to pause so that the residual currents disappear (ten minutes will be enough), then remove the side cover of the desktop PC case from the side accessing the motherboard and perform a basic dust removal. A regular vacuum cleaner with the minimum suction power set is suitable for this. When cleaning, you need to be very careful not to damage the components installed on the motherboard and the motherboard itself, otherwise the entire computer system will stop working. And replacing a motherboard is clearly not a cheap pleasure.

Problems with the graphics chip

Basically, most situations when the user hears one long and two short BIOS beeps are usually attributed to problems with the graphics adapter, since it is the adapter that is responsible for displaying the image on the screen, and if it malfunctions, problems arise with the inability to start the operating system.

In different BIOS versions (and from different developers), this sequence of signals may indicate different failures. For example, IBM BIOS issues such signals only if the computer is equipped with Mono/CGA video cards. But since such chips are practically not found today, such situations are very rare.

In the case of AST BIOS, such a sequence is issued only if problems are observed with frame scanning.

Compaq BIOS gives one long and two short beeps if initialization of the graphics adapter is not possible at all. The same situation is observed with the primary systems Award and Quadtel.

The only way to fix the problem is physically. To do this, you need to remove the video card from the corresponding slot on the motherboard and first check its functionality on another computer. If it works as expected, the slot itself may need to be cleaned. You can also try inserting it into a different connector. If the card does not work, it will have to be replaced.

Possible problems with RAM

But problems are not always related specifically to graphics adapters. For example, AMI BIOS generates one long and two short signals if problems with RAM are detected (for a video card, a sequence of pulses in combination 1-3 is used).

In this case, the memory sticks should be removed one at a time when the power is turned off, turning on the computer after each removal and checking the functionality of the system. When the damaged strip is found and the system boots in normal mode, you will simply have to replace it by installing similar equipment in its place. In this case, you should take into account which generation the RAM belongs to, and also pay attention to the characteristics of the motherboard itself in terms of ensuring that it supports the installed brackets both according to the standard and the maximum volume. Otherwise, you will not be able to use the maximum capacity, since the one determined by the motherboard may be much less.

What to do if the problem persists?

But let’s assume that it was not possible to get rid of the malfunctions using such simple methods. Let's take a situation where a Samsung laptop produces a similar combination. One long and two short BIOS signals are enough to determine problems with the hardware, but disassembling the device yourself is not always advisable.

In some cases, you can do much simpler, since the problem may be incorrect settings of the primary system. To get started, use reset parameters from the appropriate section, save the changes and check how the loading will proceed. If such actions do not give results, it may very well be that updating the BIOS will help. True, such actions must be performed competently, so as not to render the primary input/output system itself unusable.

A similar solution can be applied to stationary computer terminals. But this situation can mainly be associated with replacing hardware or installing new components, when an outdated version of the BIOS is unable to recognize modern devices. In this case, updating the firmware is the best option to fix the problem.

Instead of an afterword

It remains to add that the situation when a sequence in the form of one long and two short BIOS signals is output through the system speaker can, in principle, be corrected. Because the the real reason such behavior of the system is not explicitly indicated, you will have to perform the described actions exactly in the order in which they were given in the above material. It is advisable not to use reset and update immediately, but leave them as a last resort if the methods physical intervention will be powerless. However, first, clean up stationary unit from dust. This is the first remedy. With laptops the situation is more complicated, especially if the device is under warranty. If none of the above suggestions help, you will have to contact an authorized service center. And avoid contacting private sellers who do not have relevant repair experience. computer equipment. Then many more problems may appear.

Every time the computer boots, the system unit makes a beeping noise. Not everyone knows that this is a signal indicating the performance of the system unit. And only a few know how to decipher these signals from the system unit.

That's what we'll talk about. If you are reading this material, I recommend printing it out now. When you need decryption, you won’t be able to get online. :)

So what is the “system specialist” squeaking about? These signals are the result of testing the computer hardware (cooler, RAM, video card, etc.). Every time you boot your computer, it tests the hardware and reports the results with this particular squeak. The transcript of the system unit squeaks is below.

* One short squeak.
Explanation:
Everything is fine. The test was completed successfully. You can continue to work. It happens that some system units do not beep at all at this moment.
* There is not a squeak or image on the computer screen.
Explanation:
Malfunction in the power supply or processor.
Correction:
First, check to see if the power cord is plugged into the outlet. If everything is in order, try connecting a known working device to the surge protector (such a cord with a box in which there are many sockets, there is also a switch button, usually red). A phone charger will do, of course, with a phone connected to it. You need to check all the surge protector sockets. If the socket is working, the phone will charge. Next, we check whether the power supply starts when you press the computer start button. In this case, the cooler (fan) of the power supply should at least twitch. If there is movement, look for a new processor, otherwise, a new power supply. You also need to check the power cable of the motherboard. It may happen that he moved away.
* One long continuous squeak.
Explanation:
The power supply is faulty.
Correction:
Purchasing a new power supply.
* Two short squeaks.
Explanation:
Minor problems with BIOS settings.
Correction:
Go to BIOS and install optimal parameters. Exiting to the BIOS is usually done using the key. If you don't know what to change, then set the default values. To do this, press the button. To exit with saving - , . Some BIOS versions themselves highlight conflicting settings items by highlighting them. You can also reset the BIOS settings by removing the motherboard battery for a few seconds.
* Three long squeaks.
Explanation:
The keyboard is missing.
Correction:
Plug the keyboard into the PS/2 socket. If this does not help, you will have to change the keyboard.
* Three short squeaks.
Explanation:
RAM error.
Correction:
To do this, you need to check whether there are memory sticks on the motherboard. Don't laugh, it happens. Then you need to remove all the memory sticks, carefully sweep away the accumulated dust, and one by one stick the memory stick in and start the system unit. If the “system unit” beeps on some strip, this may mean that the strip is faulty.
* One long and one short squeak.
Explanation:
RAM is not working properly.
Correction:
Perhaps one or more memory sticks are conflicting with each other. You need to insert one memory stick at a time and try to start the computer.
* One long and two short squeaks.
Explanation:
The video adapter is not working properly.
Correction:
Correct settings in BIOS.
* One long and three short squeaks.
Explanation:
The video adapter does not work.
Correction:
Check the performance of the video card. To do this, you need another, known working video card. You can also try removing the card, removing dust from the slot, and sticking the card back in place. And don’t forget to check if the card has additional plugs for power. Power to such video cards must be supplied with a separate cord to which no device is connected. I also suggest checking whether the monitor is connected and working. Try to blow out the connector connecting the monitor to the computer.
* One long and eight short squeaks.
Explanation:
The video adapter is not working or the monitor is not connected.
Correction:
Same as written above.
* One long and nine short squeaks.
Explanation:
Error reading BIOS data.
Correction:
Try resetting the BIOS settings by removing the battery. If this does not help, then flash the BIOS. But this is another story, requiring a separate article. I'll try to write it soon.
* Four short squeaks.
Explanation:
The system timer does not work.
Correction:
You can try resetting the BIOS. But, unfortunately, it rarely helps. There is only one way out - replace or repair the motherboard.
* Five short squeaks.
Explanation:
The processor is not working properly.
Correction:
Try to clean the dust from the processor slot, make sure the heatsink is clean and the processor temperature is low.
* Six short squeaks.
Explanation:
The keyboard is faulty.
* Seven short squeaks.
Explanation:
Motherboard malfunctions.
Correction:
Have the motherboard repaired or purchase a new one.
* Eight short squeaks.
Explanation:
Problems with video memory.
Correction:
Take the video adapter for repair, or purchase a new one.
* Nine short squeaks.
Explanation:
Incorrect BIOS checksum.
Correction:
Usually it is suggested to reset the BIOS settings and allows you to continue working. If something happens, you can reset the BIOS by removing the battery.
* Ten short squeaks.
Explanation:
Error writing data to CMOS chip.
Correction:
This error may occur when flashing the BIOS. Therefore, we will describe this part in another article.
* Eleven short squeaks.
Explanation:
The cache memory is not working properly.
Correction:
Reset BIOS. If this does not help, we take the computer in for repair or install a new processor.
* Repeated long squeaks.
Explanation:
The RAM is faulty or incorrectly connected.
Correction:
Reconnecting memory sticks. Calculating the faulty one by connecting one by one and starting the computer. Cleaning from dust.
* Repeated short squeaks.
Explanation:
The power supply is not working properly.
Correction:
Checking the functionality of the power supply, checking the cords for breaks, checking the surge protector, and, last but not least, replacing the power supply.

That's all. If you have any questions, ask.

PS: To reset the BIOS, instead of removing the battery, you can use a special jumper. Its location can be found in the documentation for the motherboard.

Addition: BIOS signal encodings if the computer died.
AWARD BIOS Signals

Continuous signal. The power supply is faulty.

2 short. Minor errors found.
3 long. Keyboard controller error.
1 long + 1 short. Problems with RAM.
1 long + 2 short. Problem with the video card.
1 long + 3 short. An error occurred while initializing the keyboard.
1 long + 9 short. An error occurred while reading data from the microcircuit permanent memory.
1 long repeating. Memory modules are installed incorrectly.
1 short repeating. Problems with the power supply.

AMI BIOS signals
There are no signals. The power supply is faulty or not connected to the motherboard.
1 short. No errors found.
2 short. RAM parity error.
3 short. An error occurred during the operation of the first 64 KB of main memory.
4 short. The system timer is faulty.
5 short. The central processor is faulty.
6 short. The keyboard controller is faulty.
7 short. The motherboard is faulty.
8 short. The video memory is faulty.
9 short. BIOS chip contents checksum error.
10 short. Cannot write to CMOS memory.
11 short. The external cache memory (installed in the slots on the motherboard) is faulty.
1 long + 2 short. The video card is faulty.
1 long + 3 short. The video card is faulty.
1 long + 8 short. Problems with the video card or the monitor is not connected.

PHOENIX BIOS signals
1-1-3. CMOS data write/read error.
1-1-4. BIOS chip contents checksum error.
1-2-1. The motherboard is faulty.
1-2-2. DMA controller initialization error.
1-2-3. Error when trying to read/write to one of the DMA channels.
1-3-1. RAM regeneration error.
1-3-3. Error when testing the first 64 KB of RAM.
1-3-4. Error when testing the first 64 KB of RAM.
1-4-1. The motherboard is faulty.
1-4-2. RAM testing error.
1-4-3. System timer error.
1-4-4. Error accessing I/O port.
3-1-1. Error initializing the second DMA channel.
3-1-2. Error initializing the first DMA channel.
3-1-4. The motherboard is faulty.
3-2-4. Keyboard controller error.
3-3-4. Video memory testing error.
4-2-1. System timer error.
4-2-3. Line error A20. The keyboard controller is faulty.
4-2-4. Error when working in protected mode. The CPU may be faulty.
4-3-1. Error when testing RAM.
4-3-4. Real time clock error.
4-4-1. Serial port test failed. The error may be caused by a device using this port.
4-4-2. Error while testing parallel port. The error may be caused by a device using this port.
4-4-3. Error when testing the math coprocessor.

Compared to signals AMI audio Award signals BIOS are not so diverse, but in the vast majority of cases their set is quite enough to encode all possible motherboard errors. Distinctive features of Award BIOS are wide use long signal, as well as the use of such types of signals as continuous and constantly repeating sound signals.

Below is a list of Award beeps and their corresponding problem situations, as well as possible solutions.

• No signals

This may indicate a malfunction of both the power supply and the motherboard itself. In some cases, the system speaker of the motherboard may be faulty. To correct the situation, you can try checking the contact of the power cable coming from the power supply to the motherboard.

• One short

The user hears this signal most often. It means that the BIOS POST hardware check procedure was successful and the computer can continue booting.

• Two short

This message in Award BIOS is reserved for cases where the error is not serious and allows the computer to operate normally. A detailed text message about the essence of the error is displayed on the monitor screen. The user's further actions to resolve the error usually depend on the type of situation. For example, the error may be caused by a dead CMOS memory battery. In such a case, it must be replaced.

• Short repeating

The signal indicates a faulty power supply or damage to the power circuits. To correct the situation, you can try checking the contacts of the wires coming from the power supply to the motherboard.

• One long and one short

A message indicating a faulty RAM or no memory at all. If the latter option occurs, then the RAM modules must be installed, and if the memory is already present in the slots, then you can try to reinstall the RAM chips. If this does not help, then most likely the problem is a faulty memory module. Sometimes these signals can be generated when the video memory is faulty.

• Long repeating

An error similar to the previous one and indicating problems with RAM. This error Most often occurs when memory modules are installed incorrectly. To correct the situation, you should check whether the modules are installed correctly, and if not, then reinstall them.

• One long and two short

Similar beeps indicate a video card error. Often in such a situation, the problem is simply a poorly installed graphics accelerator card in the expansion slot, although the cause may also be a malfunction of the video card chip.

• Three long

This message means that the BIOS has detected a keyboard controller error. As in other cases, here you can try to check the connection between the keyboard and the system unit. In some cases, the signal disappears after restarting the computer again. If the keyboard works, but the signals still remain, then they can usually be turned off using special option BIOS.

• One long and three short

A sound message, like the previous one, indicating a keyboard error. But, unlike the previous error, in this case the signals indicate that the error manifests itself in a slightly different situation - the BIOS detected the keyboard, but was unable to access it.

• One long and nine short

The signals indicate a CMOS read-only memory error. This failure It can be either random, disappearing after rebooting the PC, or be a consequence of a malfunction of the CMOS memory chip, as well as incorrect flashing of the BIOS.

• Repeating signal with high and low frequencies

An error indicating a malfunction or incorrect installation of the central processor. To correct the situation, you should try to check the reliability or correct installation of the processor and its fastening in the socket.