Trouble shooting BIOS Beep Code

When your computer boot process, the computer performs a POST (Power On Self Test), which is a test that is performed each time a PC computer, is boot up. If the computer passes you will receive a normal post which in most cases is the computer beeping one or two times. However in some cases you may receive a no POST or an irregular post indicating something is causing the computer not to pass the test.

Below is a listing of some of the general steps that can be performed in helping the computer pass the POST sequence.

1)Before the irregular POST, if you added any new hardware, I would recommend it be removed to see if it is causing this issue

2)Remove all the cable from the back of the computer except for the power cable and listen to the beep codes as listed below.

3)If you continue to receive the same problem with all the above hardware still removed attempt to disconnect the CPU and RAM from the Motherboard. If this fixes the issue connect the RAM if the computer still continues to work connect the CPU.

4)If the problem persists its a good possibility that the motherboard is damaged.

The following BIOS Beep Codes were taken from the BIOS manufacturers web site.If your BIOS is not listed, you know where to go..............


Beeps Description
1-1-1-3 Verify Real Mode.
1-1-2-1 Get CPU type.
1-1-2-3 Initialize system hardware.
1-1-3-1 Initialize chipset registers with initial POST values.
1-1-3-2 Set in POST flag.
1-1-3-3 Initialize CPU registers.
1-1-4-1 Initialize cache to initial POST values.
1-1-4-3 Initialize I/O.
1-2-1-1 Initialize Power Management.
1-2-1-2 Load alternate registers with initial POST values.
1-2-1-3 Jump to UserPatch0.
1-2-2-1 Initialize keyboard controller.
1-2-2-3 BIOS ROM checksum.
1-2-3-1 8254 timer initialization.
1-2-3-3 8237 DMA controller initialization.
1-2-4-1 Reset Programmable Interrupt Controller.
1-3-1-1 Test DRAM refresh.
1-3-1-3 Test 8742 Keyboard Controller.
1-3-2-1 Set ES segment to register to 4 GB.
1-3-3-1 28 Autosize DRAM.
1-3-3-3 Clear 512K base RAM.
1-3-4-1 Test 512 base address lines.
1-3-4-3 Test 512K base memory.
1-4-1-3 Test CPU bus-clock frequency.
1-4-2-4 Reinitialize the chipset.
1-4-3-1 Shadow system BIOS ROM.
1-4-3-2 Reinitialize the cache.
1-4-3-3 Autosize cache.
1-4-4-1 Configure advanced chipset registers.
1-4-4-2 Load alternate registers with CMOS values.
2-1-1-1 Set Initial CPU speed.
2-1-1-3 Initialize interrupt vectors.
2-1-2-1 Initialize BIOS interrupts.
2-1-2-3 Check ROM copyright notice.
2-1-2-4 Initialize manager for PCI Options ROMs.
2-1-3-1 Check video configuration against CMOS.
2-1-3-2 Initialize PCI bus and devices.
2-1-3-3 Initialize all video adapters in system.
2-1-4-1 Shadow video BIOS ROM.
2-1-4-3 Display copyright notice.
2-2-1-1 Display CPU type and speed.
2-2-1-3 Test keyboard.
2-2-2-1 Set key click if enabled.
2-2-2-3 56 Enable keyboard.
2-2-3-1 Test for unexpected interrupts.
2-2-3-3 Display prompt "Press F2 to enter SETUP".
2-2-4-1 Test RAM between 512 and 640k.
2-3-1-1 Test expanded memory.
2-3-1-3 Test extended memory address lines.
2-3-2-1 Jump to UserPatch1.
2-3-2-3 Configure advanced cache registers.
2-3-3-1 Enable external and CPU caches.
2-3-3-3 Display external cache size.
2-3-4-1 Display shadow message.
2-3-4-3 Display non-disposable segments.
2-4-1-1 Display error messages.
2-4-1-3 Check for configuration errors.
2-4-2-1 Test real-time clock.
2-4-2-3 Check for keyboard errors
2-4-4-1 Set up hardware interrupts vectors.
2-4-4-3 Test coprocessor if present.
3-1-1-1 Disable onboard I/O ports.
3-1-1-3 Detect and install external RS232 ports.
3-1-2-1 Detect and install external parallel ports.
3-1-2-3 Re-initialize onboard I/O ports.
3-1-3-1 Initialize BIOS Data Area.
3-1-3-3 Initialize Extended BIOS Data Area.
3-1-4-1 Initialize floppy controller.
3-2-1-1 Initialize hard-disk controller.
3-2-1-2 Initialize local-bus hard-disk controller.
3-2-1-3 Jump to UserPatch2.
3-2-2-1 Disable A20 address line.
3-2-2-3 Clear huge ES segment register.
3-2-3-1 Search for option ROMs.
3-2-3-3 Shadow option ROMs.
3-2-4-1 Set up Power Management.
3-2-4-3 Enable hardware interrupts.
3-3-1-1 Set time of day.
3-3-1-3 Check key lock.
3-3-3-1 Erase F2 prompt.
3-3-3-3 Scan for F2 key stroke.
3-3-4-1 Enter SETUP.
3-3-4-3 Clear in-POST flag.
3-4-1-1 Check for errors
3-4-1-3 POST done--prepare to boot operating system.
3-4-2-1 One beep.
3-4-2-3 Check password (optional).
3-4-3-1 Clear global descriptor table.
3-4-4-1 Clear parity checkers.
3-4-4-3 Clear screen (optional).
3-4-4-4 Check virus and backup reminders.
4-1-1-1 Try to boot with INT 19.
4-2-1-1 Interrupt handler error.
4-2-1-3 Unknown interrupt error.
4-2-2-1 Pending interrupt error.
4-2-2-3 Initialize option ROM error.
4-2-3-1 Shutdown error.
4-2-3-3 Extended Block Move.
4-2-4-1 Shutdown 10 error.
4-3-1-3 Initialize the chipset.
4-3-1-4 Initialize refresh counter.
4-3-2-1 Check for Forced Flash.
4-3-2-2 Check HW status of ROM.
4-3-2-3 BIOS ROM is OK.
4-3-2-4 Do a complete RAM test.
4-3-3-1 Do OEM initialization.
4-3-3-2 Initialize interrupt controller.
4-3-3-3 Read in bootstrap code.
4-3-3-4 Initialize all vectors.
4-3-4-1 Boot the Flash program.
4-3-4-2 Initialize the boot device.
4-3-4-3 Boot code was read OK.


Error Tone. (two sets of different tones)
Problem with logic board or SCSI bus.

Startup tone, drive spins, no video
Problem with video controller.

Powers on, no tone.
Logic board problem.

High Tone, four higher tones.
Problem with SIMM


Beep Code/Description

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.


Beep Code/Description
1 long, 2 short I
ndicates a video error has occurred and the BIOS cannot initialise the
video screen to display any additional information

Any other beep(s)
RAM problem.


Beep Code/Descriptions
1 short
DRAM refresh failure

2 short
Parity circuit failure

3 short
Base 64K RAM failure

4 short
System timer failure

5 short
Process failure

6 short
Keyboard controller Gate A20 error

7 short
Virtual mode exception error

8 short
Display memory Read/Write test failure

9 short
ROM BIOS checksum failure

10 short
CMOS shutdown Read/Write error

11 short
Cache Memory error

1 long, 3 short
Conventional/Extended memory failure

1 long, 8 short
Display/Retrace test failed

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