What the BIOS signals mean

2024 Author: Malcolm Clapton | [email protected]. Last modified: 2023-12-17 03:44

Decode obscure sounds and find out what the computer is trying to tell you.

Why is the computer beeping

Each time the PC is turned on, the hardware POST (Power On Self Test) is started, and if errors are found, they are displayed on the screen. However, if failures occur even before the output system is loaded and the monitor is turned on, then beeps are used to indicate errors.

They are served by the system speaker located on the motherboard. Alarms are a series of high-frequency beeps, similar to the ringtones of old mobile phones or the sounds of a cheap Chinese alarm clock.

What to do if you hear a squeak from your PC

In case of malfunctions accompanied by sound signals, for their further diagnosis, you need to do the following.

• Turn on the computer or reboot with the Reset button if it is already on.
• Listen carefully to the emitted signals. Restart your PC if necessary to reproduce the error again.
• Write down the combination of sounds on paper. Duration, number of signals, pauses between them - all this is important.
• Check the BIOS manufacturer for your computer. To do this, first check the model of the motherboard in the documentation or by marking on the device itself. And then search the Internet for which vendor BIOS is used in the motherboard. In most cases, hardware and BIOS designers are different.
• Knowing the manufacturer of the system software, find the error code using the signal combinations below.

For example, when the computer is turned on, it quickly beeps three times in a row - three short signals are obtained. We open the side cover of the system unit and carefully look at the markings on the motherboard. We see Gigabyte GA-970A-DS3P. Next, we are looking for information on this model and find out that it uses the BIOS from American Megatrends, that is, AMI. We find our code in the corresponding section and find out that the problems are caused by an error in the RAM.

How to decode BIOS signals

One short beep usually indicates a successful test completion, all others indicate a certain hardware error. Signals and their meanings may vary depending on the BIOS manufacturer.

AMI BIOS codes

Many component manufacturers use BIOS from American Megatrends. Some manufacturers integrate their own software based on AMI BIOS, in which case the interpretation of certain signals may not be the same.

• 1 short - memory update error.
• 2 short - problems with RAM.
• 3 short - error reading the first 64 KB of memory.
• 4 short - failure of the system timer.
• 5 short - processor error.
• 6 short - keyboard controller malfunctions.
• 7 short - error on the system board or external hardware.
• 8 short - failure to read-write video memory.
• 9 short - Invalid BIOS checksum.
• 10 short - error writing ‑ reading CMOS ‑ memory.
• 11 short - failure of the cache memory.
• 1 long, 3 short - video adapter error.
• 1 long, 8 short - problems with the video card or monitor.
• Siren sound - low speed of the processor fan, problems with the power supply.

PhoenixBIOS codes

System software from Phoenix Technologies is used by most modern motherboard manufacturers. There are modified versions of PhoenixBIOS based on the original software. The meaning of the codes in them is the same, but sometimes it can be slightly different.

This type of BIOS uses signals of the same length, which are separated by pauses. Code 1-3-1 should be read as one beep, pause, three beeps, pause, one beep.

• 1–1–2 - Failure to initialize the processor.
• 1–1–3 - error of reading-writing of CMOS memory.
• 1–1–4 - Invalid BIOS checksum.
• 1–2–1 - failed to initialize the motherboard.
• 1–2–2, 1–2–3 - DMA controller error.
• 1–3–1 - failure to initialize the memory regeneration circuit.
• 1–3–3, 1–3–4 - Failure to initialize the first 64 KB of memory.
• 1–4–1 - motherboard initialization error.
• 1–4–2 - failure to initialize RAM.
• 1–4–3, 4–2–1 - error initializing the system timer.
• 1–4–4 - failure to read ‑ write the I / O port.
• 2–1–1, 2–1–2, 2–1–3, 2–1–4, 2–2–1, 2–2–2, 2–2–3, 2–2–4, 2–3–1, 2–3–2, 2–3–3, 2–3–4, 2–4–1, 2–4–2, 2–4–3, 2–4–4 - error of reading the memory record.
• 3–1–1, 3–1–2, 3–1–4 - Failure to initialize the DMA channel.
• 3–2–4, 4–2–3 - an error in the initialization of the keyboard controller.
• 3–3–4, 3–4–1 - problems with video memory.
• 3–4–2 - failure to initialize the video adapter.
• 4–2–4 - error when enabling the protected mode of the processor.
• 4–3–1 - failure to initialize RAM.
• 4–3–2, 4–3–3 - problems with the system timer.
• 4–4–1 - error initializing the serial port.
• 4–4–2 - failed to initialize the parallel port.
• 4–4–3 - coprocessor initialization error.
• Cyclic signals - problems with the motherboard.
• Siren sound - failure or breakdown of the video adapter.
• Continuous signal - the processor fan does not work or is disabled.

Award BIOS codes

Award BIOS is now owned by Phoenix Technologies, but is often found on older hardware. There are firmware options that have been modified by the motherboard manufacturer. As a rule, the description of the codes in them is the same.

• 1 short - no errors, successful download.
• 1 long, 2 short - video memory initialization error.
• 1 long, 3 short - The video adapter was not found or has a problem.
• Endless signal - RAM failure.
• Siren sound - processor error or damage.