How to recognize beep errors

[spookshow]

AMI BIOS beep codes
Award BIOS beep codes
IBM BIOS beep codes
Phoenix BIOS Post codes
Other Post codes

Annoying isn't it? You have built your computer you switch it on and then nothing happens except a few beeps from the PC speaker. Frustration sets in as you try to figure out what is wrong with it. If you didn't already know the computer has already told you the problem. It can't speak of course but it can direct you to the problem. Its all in the beeps. The BIOS can recognise when the problem occurs and sends a signal out to send a certain amount of beeps through the speaker. These beeps then tell you the location of the problem.

Unfortunately not all the BIOS' use the same codes as each other. Two of the main BIOS manufactures AMI and Award (now Phoenix) have different codes for there errors.

AMI BIOS BEEP CODES

The following are AMI BIOS Beep Codes that can occur. However because of the wide variety of different computer manufacturers with this BIOS the beep codes may vary.

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

[spookshow]

AWARD BIOS BEEP CODES

The following are Award BIOS Beep Codes that can occur. However because of the wide variety of different computer manufacturers with this BIOS the beep codes may vary.

Beep Code Description

• 1 long, 2 short : Indicates a video error has occurred and the BIOS cannot initialize the video screen to display any additional information
• Repeating beeps : Memory Error - Memory is either damaged or badly seated
• Repeating Hi/Low Beeps: Damaged or Overheating CPU
• Hi Frequency Beeps: Overheating CPU

If any other correctable hardware issues the BIOS will display a message.

[spookshow]

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 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.

The IBM BIOS works with Short and Long beeps as well as the Award BIOS. However the IBM one does still have codes to work from.

[spookshow]

PHOENIX BIOS BEEP CODES

The following is for PHOENIX BIOS Q3.07 OR 4.X

Beep Code Description / What to Check

• 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 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.

[spookshow]

MACINTOSH STARTUP TONES

TONES ERROR

• 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.

[spookshow]

Each time the computer boots up the computer must past the POST. Below is the common steps a POST performs each time your computer starts.

1. Test the power supply to ensure that it is turned on and that it releases its reset signal.
2. CPU must exit the reset status mode and thereafter be able to execute instructions.
3. BIOS checksum must be valid, meaning that it must be readable.
4. CMOS checksum must be valid, meaning that it must be readable.
5. CPU must be able to read all forms of memory such as the memory controller, memory bus, and memory module.
6. The first 64KB of memory must be operational and have the capability to be read and written to and from, and capable of containing the POST code.
7. I/O bus / controller must be accessible.
8. I/O bus must be able to write / read from the video subsystem and be able to read all video RAM.

If the computer does not pass any of the above tests, your computer will receive an irregular POST. An irregular POST is a beep code that is different from the standard one or two beeps. This could be either no beeps at all or a combination of different beeps indicating what is causing the computer not to past the POST.