1 short beep

Normal POST - system is ok

2 short beeps

POST Error - error code shown on screen

No beep

Power supply or system board problem

Continuous beep

Power supply, system board, or keyboard problem

Repeating short beeps

Power supply or system board problem

1 long, 1 short beep

System board problem

1 long, 2 short beeps

Display adapter problem (MDA, CGA)

1 long, 3 short beeps

Enhanced  Graphics Adapter (EGA)

3 long beeps

3270 keyboard card

 100 - 199

System Board

200 - 299

Memory

300 - 399

Keyboard

400 - 499

Monochrome Display

500 - 599

Color/Graphics Display

600 - 699

Floppy-disk drive and/or Adapter

700 - 799

Math Coprocessor

900 - 999

Parallel Printer Port

1000 - 1099

Alternate Printer Adapter

1100 - 1299

Asynchronous Communication Device, Adapter, or Port

1300 - 1399

Game Port

1400 - 1499

Color/Graphics Printer

1500 - 1599

Synchronous Communication Device, Adapter, or Port

1700 - 1799

Hard Drive and/or Adapter

1800 - 1899

Expansion Unit (XT)

2000 - 2199

Bisynchronous Communication Adapter

2400 - 2599

EGA system-board Video (MCA)

3000 - 3199

LAN Adapter

4800 - 4999

Internal Modem

7000 - 7099

Phoenix BIOS Chips

7300 - 7399

3.5" Disk Drive

8900 - 8999

MIDI Adapter

11200 - 11299

SCSI Adapter

21000 - 21099

SCSI Fixed Disk and Controller

21500 - 21599

SCSI CD-ROM System

 1 Short Beep

One beep is good! Everything is ok, that is if you see things on the screen. If you don't see anything, check your monitor and video card first. Is everything connected? If they seem fine, your motherboard has some bad chips on it. First reset the SIMM's and reboot. If it does the same thing, one of the memory chips on the motherboard are bad, and you most likely need to get another motherboard since these chips are soldered on. 

2 Short Beeps

 Your computer has memory problems. First check video. If video is working, you'll see an error message. If not, you have a parity error in your first 64K of memory. First check your SIMM's. Reseat them and reboot. If this doesn't do it, the memory chips may be bad. You can try switching the first and second banks memory chips. First banks are the memory banks that your CPU finds its first 64K of base memory in. You'll need to consult your manual to see which bank is first. If all your memory tests good, you probably need to buy another motherboard. 

3 Short Beeps

Basically the same thing as 2 beeps. Follow that diagnosis above. 

4 Short Beeps

Basically the same thing as 2 beeps. Follow that diagnosis above. It could also be a bad timer 

5 Short Beeps

Your motherboard is complaining. Try reseating the memory and rebooting. If that doesn't help, you should consider another motherboard. You could probably get away with just replacing the CPU, but that's not too cost-effective. Its just time to upgrade! 

6 Short Beeps

The chip on your motherboard that controls your keyboard (A20 gate) isn't working. First try another keyboard. If it doesn't help, reseat the chip that controls the keyboard, if it isn't soldered in. If it still beeps, replace the chip if possible. Replace the motherboard if it is soldered in. 

7 Short Beeps

Your CPU broke overnight. Its no good. Either replace the CPU, or buy another motherboard. 

8 Short Beeps

Your video card isn't working. Make sure it is seated well in the bus. If it still beeps, either the whole card is bad or the memory on it is. Best bet is to install another video card. 

9 Short Beeps

Your BIOS is bad. Reseat or Replace the BIOS. 

10 Short Beeps

Your problem lies deep inside the CMOS. All chips associated with the CMOS will likely have to be replaced. Your best bet is to get a new motherboard.

11 Short Beeps

Your problem is in the Cache Memory chips on the motherboard. Reseat or Replace these chips.

1 Long, 3 Short Beeps

You've probably just added memory to the motherboard since this is a conventional or extended memory failure. Generally this is caused by a memory chip that is not seated properly. Reseat the memory chips.

1 Long, 8 Short Beeps

Display / retrace test failed. Reseat the video card.

1-1-3

Your computer can't read the configuration info stored in the CMOS. Replace the motherboard. 

1-1-4

Your BIOS needs to be replaced. 

1-2-1

You have a bad timer chip on the motherboard. You need a new motherboard. 

1-2-2

The motherboard is bad. 

1-2-3

The motherboard is bad. 

1-3-1

You'll need to replace the motherboard. 

1-3-3

You'll need to replace the motherboard. 

1-3-4 

The motherboard is bad. 

1-4-1

The motherboard is bad. 

1-4-2 

Some of your memory is bad. 

2-_-_ 

Any combo of beeps after two means that some of your memory is bad, and unless you want to get real technical, you should probably have the guys in the lab coats test the memory for you. Take it to the shop. 

3-1-_ 

One of the chips on your motherboard is broken. You'll likely need to get another board. 

3-2-4

One of the chips on your motherboard that checks the keyboard is broken. You'll likely need to get another board. 

3-3-4

Your computer can't find the video card. Is it there? If so, try swapping it with another one and see if it works. 

3-4-_ 

Your video card isn't working. You'll need to replace it. 

4-2-1

There's a bad chip on the motherboard. You need to buy another board. 

4-2-2

First check the keyboard for problems. If nothing, you have a bad motherboard. 

4-2-3 

Same as 4-2-2. 

4-2-4 

One of the cards is bad. Try yanking out the cards one by one to isolate the culprit. Replace the bad one. The last possibility is to buy another motherboard. 

4-3-1

Replace the motherboard. 

4-3-2

See 4-3-1

4-3-3

See 4-3-1

4-3-4

Time of day clock failure. Try running the setup program that comes with the computer. Check the date and time. If that doesn't work, replace the battery. If that doesn't work, replace the power supply. You may have to replace the motherboard, but that is rare. 

4-4-1

Your serial ports are acting up. Reseat, or replace, the I/O card. If the I/O is on the motherboard itself, disable them with a jumper (consult your manual to know which one) and then add an I/O card. 

4-4-2

See 4-4-1, but this time is your Parallel port that's acting up.

4-4-3

You math coprocessor is having problems. Run a test program to double-check it. If it is indeed bad, disable it, or replace it.

Low 1-1-2

Your motherboard is having problems

Low 1-1-3

This is an Extended CMOS RAM problem, check your motherboard battery, and motherboard.