BIOS POST Tone Error Codes

What is all that beep, beep, supposed to mean?
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This material is presented only as a description of how I go about working on a system. It is not meant to encourage unqualified personnel to attempt computer repair. In any event, you assume all responsibility and liability for injury or damage.

Anthony Olszewski

AMI BIOS Tone POST Codes -- Fatal Errors
1 shortDRAM refresh
2 short Parity circuit
3 short Base 64K RAM
4 short System timer
5 short Processor
6 short Keyboard controller gate A20
7 short Virtual mode exception
8 short Display memory read/write test
9 short ROM BIOS checksum
10 short CMOS shutdown read/write
11 short Cache memory

AMI BIOS Tone POST Codes -- Non-Fatal Errors
1 long, 3 short Conventional/extended memory
1 long, 8 short Display/retrace test

Phoenix BIOS Tone POST Codes -- Fatal Errors
None CPU register test
None First 64K RAM test
None Interrupt vector loading proceeding
None CMOS power failure/checksum calculation
None Display configuration validation proceeding
None Display running with video ROM
None Display functional
None Mononchrome display functional
None CGA display functional
1-1-3 CMOS write/read
1-1-4 ROM BIOS checksum
1-2-1 Programmable interval timer
1-2-2 DMA Initialization
1-2-3 DMA page register write/read
1-3-1 RAM refresh verification
1-3-3 First 64K RAM chip or data line
1-3-4 First 64K RAM odd/even logic
1-4-1 Address line first 64K RAM
1-4-2 Parity failure first 64K RAM
2-1-1 Bit 0, first 64K RAM
2-1-2 Bit 1, first 64K RAM
2-1-3 Bit 2, first 64K RAM
2-1-4 Bit 3, first 64K RAM
2-2-1 Bit 4, first 64K RAM
2-2-2 Bit 5, first 64K RAM
2-2-3 Bit 6, first 64K RAM
2-2-4 Bit 7, first 64K RAM
2-3-1 Bit 8, first 64K RAM
2-3-2 Bit 9, first 64K RAM
2-3-3 Bit 10, first 64K RAM
2-3-4 Bit 11, first 64K RAM
2-4-1 Bit 12, first 64K RAM
2-4-2 Bit 13, first 64K RAM
2-4-3 Bit 14, first 64K RAM
2-4-4 Bit 15, first 64K RAM
3-1-1 Slave DMA register
3-1-2 Master DMA register
3-1-3 Master interrupt mask register
3-1-4 Slave interrupt mask register
3-2-4 Keyboard controller
3-3-4 Display initialization
3-4-1 Display retrace
3-4-2 Search for video ROM proceeding

Phoenix BIOS POST Tone Codes -- Non-Fatal Errors
4-2-1 Timer tick interrupt test
4-2-2 Shutdown test
4-2-3 Gate A20 Failure
4-2-4 Unexpected interrupt in protected moe
4-3-1 RAM test (address failure >FFFFh)
4-3-3 Interval timer channel 2
4-3-4 Real time clock
4-4-1 Serial Port
4-4-2 Parallel Port
4-4-3 Math Co-processor test
1-1-2* System board select
1-1-3* Extender CMOS RAM
*audio code pattern preceded by low pitched tone

IBM POST Tone Codes
NONE System board, power supply
1 short System passed all tests
2 short Display error
continuous System board, power supply
1 long, 1 short System board
1 long, 2 short Video adapter
1 long, 3 short EGA
3 long 3270 keyboard card