Computer beep codes and their meanings

Computer POST and Beep code

Definition of: beep codes

Some number of short beeps that are sounded by the BIOS upon startup when a memory, cache or processor error is encountered. There are numerous beep code patterns, and Phoenix BIOS codes are long and short beeps delivered in groups. The following beep codes are for AMI BIOSs. There are additional beep codes for this BIOS not included here. See BIOS and POST card

1 Beep - Refresh Failure
Reset/replace memory, troubleshoot motherboard.

2 Beeps - Parity Error
Reset/replace memory, troubleshoot motherboard.

3 Beeps - Memory Error (first 64KB)
Reset/replace memory.

4 Beeps - Timer Failure
Troubleshoot motherboard.

5 Beeps - Processor Failure
Troubleshoot CPU, motherboard.

6 Beeps - Keyboard Controller Failure
Troubleshoot keyboard, motherboard.

7 Beeps - Virtual Mode Exception Error
Troubleshoot CPU, motherboard.

8 Beeps - Display Memory Failure
Troubleshoot graphics card, motherboard.

9 Beeps - ROM BIOS Checksum Failure
Replace ROM BIOS, troubleshoot motherboard.

10 Beeps - CMOS Shutdown Register Failure
Troubleshoot motherboard.

11 Beeps - L2 Cache Failure
Troubleshoot L2 cache, motherboard.

Continuous Beeps - Memory or Video Failure
Troubleshoot memory, graphics card, motherboard.

WINBIOS

The following are win BIOS Beep Codes that can occur.

Beeps	Error Message	Description	Resolution
1	Refresh Failure	The memory refresh circuitry is faulty.	Reset the memory SIMMs. If the system still beeps, replace the memory.
2	Parity Error	Parity error in the base memory (the first 64 KB block) of memory.	Reset the memory SIMMs. If the system still beeps, replace the memory.
3	Base 64 KB Memory Failure	Memory failure in first 64 KB.	Reset the memory SIMMs. If the system still beeps, replace the memory.
4	Timer Not Operational	A memory failure in the first 64 KB of memory, or Timer 1 is not functioning.	The motherboard must be replaced.
5	Processor error 8042 - Gate A20 Failure	The CPU generated an error.	The motherboard must be replaced.
6	8042 - Gate A20 Failure Processor Exception Interrupt Error	Cannot switch to protected mode.	Try a different keyboard, or replace the keyboard fuse, if the keyboard has one.
7	Processor Exception Interrupt Error	The CPU on the CPU Card generated an exception interrupt.	The motherboard must be replaced.
8	Display Memory Read/Write Error	The system video adapter is either missing or its memory is faulty. This is not a fatal error.	There is a memory error on the video adapter. Replace the video adapter, or the RAM on the video adapter.
9	ROM Checksum Error	The ROM checksum value does not match the value encoded in WINBIOS.	The BIOS ROM chip is bad. The system probably needs a new BIOS ROM chip.
10	CMOS Shutdown Register Read/Write Error	The shutdown register for CMOS RAM has failed.	The motherboard must be replaced.
11	Cache memory bad - do not enable cache	The cache memory test failed. Cache memory is disabled. Do not press Ctrl/Alt/Shift <+> to enable cache memory.	The motherboard must be replaced.

IBM BIOS

The following are IBM BIOS Beep Codes that can occur. However because of the wide variety of models shipping with this BIOS the beep codes may vary.

Beep Code	Descriptions
No Beeps	No Power, Loose Card, or Short.
1 Short Beep	Normal POST, computer is ok.
2 Short Beep	POST error, review screen for error code.
Continuous Beep	No Power, Loose Card, or Short.
Repeating Short Beep	No Power, Loose Card, or Short.
One Long and one Short Beep	Motherboard issue.
One Long and Two short Beeps	Video (Mono/CGA Display Circuitry) issue.
One Long and Three Short Beeps.	Video (EGA) Display Circuitry.
Three Long Beeps	Keyboard / Keyboard card error.
One Beep, Blank or Incorrect Display	Video Display Circuitry.