The Hardware Guide
Tips, tricks and tweaks for getting the most out of your hardware.
Motherboard Beep Codes

Standard Original IBM POST Error Codes
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 beepsPower supply or system board problem
1 long, 1 short beep System board problem
1 long, 2 short beepsDisplay adapter problem (MDA, CGA)
1 long, 3 short beepsEnhanced Graphics Adapter (EGA)
3 long beeps 3270 keyboard card

AMI BIOS Beep Codes
1 Short BeepOne 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 BeepsBasically the same thing as 2 beeps. Follow that diagnosis above.
4 Short BeepsBasically the same thing as 2 beeps. Follow that diagnosis above. It could also be a bad timer
5 Short BeepsYour 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 BeepsThe 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 BeepsYour CPU broke overnight. Its no good. Either replace the CPU, or buy another motherboard.
8 Short BeepsYour 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 BeepsYour BIOS is bad. Reseat or Replace the BIOS.
10 Short BeepsYour 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 BeepsYour problem is in the Cache Memory chips on the motherboard. Reseat or Replace these chips.
1 Long, 3 Short BeepsYou'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 BeepsDisplay / retrace test failed. Reseat the video card.

Phoenix BIOS Beep Codes
1-1-3Your computer can't read the configuration info stored in the CMOS. Replace the motherboard.
1-1-4Your BIOS needs to be replaced.
1-2-1You have a bad timer chip on the motherboard. You need a new motherboard.
1-2-2The motherboard is bad.
1-2-3The motherboard is bad.
1-3-1You'll need to replace the motherboard.
1-3-3You'll need to replace the motherboard.
1-3-4 The motherboard is bad.
1-4-1The 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.
3-2-4One of the chips on your motherboard that checks the keyboard is broken. You'll likely need to get another board.
3-3-4Your 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.
4-2-1There's a bad chip on the motherboard. You need to buy another board.
4-2-2First 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.
4-3-1Replace the motherboard.
4-3-2See 4-3-1
4-3-3See 4-3-1
4-3-4Time 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.
4-4-1Your 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.
4-4-2See 4-4-1, but this time is your Parallel port that's acting up.
4-4-3You math coprocessor is having problems. Run a test program to double-check it. If it is indeed bad, disable it, or replace it.
Low 1-1-2Your motherboard is having problems
Low 1-1-3This is an Extended CMOS RAM problem, check your motherboard battery, and motherboard.