A beep code is an audio signal emitted by the Basic Input/Output System (BIOS) of a computer to announce the result of a short, diagnostic testing sequence. When a computer first starts up, it runs a Power-On Self Test (POST), a small program contained in the computer’s BIOS. If an error occurs, an error message will display on the screen. However, if BIOS encounters an error but hasn’t booted up far enough to be able to display a POST error message, a beep will sound instead.
Beep patterns vary according to the manufacturer of the computer’s program, so there is no official standard. Regardless of the beep pattern, the beeping sequence is essentially a coded message that tells the user what is wrong with the computer.
Beep code meanings for different bios
As mentioned, beep patterns are different depending on the manufacturer. Also, the beep sounds themselves could be long or short, continuous or pulsing, and high or low. Beep patterns and their meanings per manufacturer are listed below.
Award/Phoenix beep codes
- 1 short beep: No errors detected during self-test
- 2 short beeps: Non-specified error
- Continuous beep: Memory or graphics card not detected
- Repeated short beeps: Inadequate power supplied to motherboard
- 1 long beep: RAM error
- 1 long, 1 short beep: Motherboard error
- 1 long, 2 short beeps: Graphics card error
- 1 long, 3 short beeps: Keyboard controller failure or graphics card error in later versions
- 3 long beeps: Communication error between keyboard and motherboard
AMI beep codes
- 1 short beep: Incorrect interaction between RAM and motherboard
- 1 long beep: No errors detected during self-test
- Continuous beep: Power supply error
- 1 long, 1 short beep: Fault on motherboard
- 1 long, 2 short beeps: Graphics cards not detected
- 1 long, 3 short beeps: Video memory error
- 2 short beeps: Parity error in the first 64 KB of memory
- 2 long, 2 short beeps: Video memory error
- 3 short, 3 long, 3 short beeps: Defective RAM, must be replaced
- 5 short beeps: Problem with processor
- 6 short beeps: Cannot enter BIOS in safe mode
- 7 short beeps: Processor or graphics card error
- 8 short beeps: Display memory error in graphics card
- 9 short beeps: CMOS battery error
- 10 short beeps: Error in shutdown register of CMOS RAM
- 11 short beeps: Error in external cache memory
IBM beep codes
- 1 short beep: no errors detected during self-test
- 2 short beeps: Error during POST
- No beep: Power supply/system board/processor error. Often related to power supply
- Continuous beep: Power supply/system board/keyboard problem
- Repeated short beeps: Power supply or system board problem
- 1 long, 1 short beep: System board problem
- 1 long, 2 short beeps: Graphics card problem (Mono/CGA video error)
- 1 long, 3 short beeps: Graphics card problem (EGA video error)
- 3 long beeps: Keyboard problem
DELL beep codes
Dell beep codes are all the same length. To identify the error, listen for how often a beep is repeated after a pause. The beeps come in segments.
- 1 – 1 – 2 (“beep – beep – beep beep”): Microprocessor register failure
- 3 – 2 – 4: Keyboard controlled test failure
- 3 – 3 – 1: NVRAM power loss
- 3 – 3 – 4: Video memory test failure
- 3 – 4 – 1: Screen initialization failure
- 4 – 2 – 2: Shutdown failure
- 4 – 4 – 4: Cache test failure
Macintosh beep codes
- One beep every 5 seconds: No RAM installed
- 3 short beeps, 5 second pause, 3 short beeps: RAM did not pass integrity check
- 3 long, 2 short, 3 long beeps: EFI ROM error or Mac is in EFI ROM recovery mode
MR beep codes
MR systems use high (H) and low (L) beeps. The dashed indicate pauses.
- LH – LLL – BIOS failure, replacement required
- LH – HLL: DMA page register failure
- LH – LHL: Keyboard controller self-test failure
- LH – HHL: RAM seated incorrectly
- LH – LLH: Mainboard failure
- LH – LLL: Memory bank 0 pattern failure
- LH – LHLLH: CMOS RAM read/write test failure
- LH – HHLLH: Real-time clock failure
- LH – LLHLH: BIOS/RAM failure with graphics card
- LH – HLHLH: Keyboard controller failure
- LH – LHHLH – RAM parity error
