General Question

bomyne's avatar

What do three long beeps when booting a PC mean?

Asked by bomyne (489 points ) May 7th, 2014

I have a custom built PC. It’s been working fine for three years, with only one or two minor problems. i shut it down last night and didn’t touch it until this afternoon. When I pressed the power button, The LEDs in the computer came on, all the fans spun… but the keyboard and monitors did not light up and I heard three long beeps from the system. In the background i can hear harddrive activity that is consistent with Windows 7 going though it’s boot process, but there is still nothing from the monitors or the keyboard. The power button acts as if Windows has taken control of it, so I hold it down to power off, then turn it back on and get the same response. Three long beeps.

I have not adjusted the hardware in the last three months since i replaced the power supply. Does anyone know what is happening? Thank you.

Observing members: 0 Composing members: 0

36 Answers

BosM's avatar

When you turn on your computer, and it continually beeps three times (three one-second beeps), it means there is a memory issue. To resolve this problem, check the following:

•Make sure the memory modules are properly installed in the DIMM slots, and that they are pressed in completely with the latches locked in place.

•Make sure you are using supported memory for your board. Verify speed/size of memory.

•Check that the memory modules are not defective: ◦test memory modules one at a time.
◦Try modules in another computer or try different known-working modules in this system.

http://www.intel.com/support/motherboards/desktop/sb/CS-034262.htm

BhacSsylan's avatar

Check who manufactures your motherboard. While @BosM may be right, it depends on who manufactures it as to what that beep means. Most board do have three beeps as a memory issue, but from the sound of the symptoms it sounds more like your video card is dead, so just check to be sure. If it is memory, trying to reseat would probably be good, followed by swapping out some if you have 4 or trying on a different system if you have one handy.

ARE_you_kidding_me's avatar

Who makes your bios? You cannot be sure until you verify the software company. It will be someone like award, msi… the generic ibm code for three long beeps indicates a keyboard error.

CWOTUS's avatar

What you’re hearing is part of the POST routine. POST = Power-On Self-Test. Every time you reboot the computer and it starts up, it runs through its POST (as long as that isn’t aborted in some way). Usually this means next to nothing to you, as the computer starts, you log in normally and go. Now you’re having to learn about POST, however.

When the computer cannot communicate with you normally via the console (the screen) and keyboard, it sends audible tones such as you describe. For various BIOS (Basic Input/Output System) manufacturers, the tones mean different things. (Or they used to; they may be pretty well standardized by now; my first experience with POST routines probably predates your birth and does predate color monitors.)

But to sort of synthesize the various responses that you’ve seen so far, Google the manufacturer of your BIOS for its POST codes, and when you find the right reference it will tell you exactly what “three long tones” means. If you’re lucky, it may even tell you how to resolve the issue. I’m not so certain as @BosM that it’s a memory issue, because usually that information can be communicated via the console. It’s very likely that your video card (or its memory) has a problem. I do think it’s a video problem, based on the fact that… you have no video.

flip86's avatar

Sorry to tell you this, but you may have fried the MOBO with the new PSU. You most likely need to replace the computer. Look at it this way, at least it wasn’t the HDD that went. All your data is still there.

bomyne's avatar

How can i test the video card? I mean, there’s no onboard video and i do not have another computer that i can swap the card with. I am also 50KM from the closest computer shop so i’d rather try and fix this without taking it in, and take it in as a last resort.

I’m having trouble finding the box the motherboard came in but i’m going to keep looking so i can google it as you have suggested.

Thanks all.

BhacSsylan's avatar

Can you open then case easily to read the motherboard? Usually they are branded in a way to make it easy to figure out. As for looking at the card, if it doesn’t have graphics onboard you’ll need to swap it out somehow, either with another card or into another machine, sorry.

And I seriously disagree with @flip86. Not sure why you’d think that at all, really.

Also, if he did fry it, he could simply replace it. Much cheaper than replacing the whole computer, by several hundred dollars at least.

flip86's avatar

@BhacSsylan Cheap PSU’s are known to short out components. The PSU may have shorted out the memory slot, which would make it a MOBO problem, not a memory problem.

BhacSsylan's avatar

Why do you assume it’s cheap, or that it didn’t fry the memory itself, if that’s even the case? It’s quite a leap to go from ‘bios is functioning and monitor doesn’t work’ to ‘your mobo is fried, chuck the whole thing’. Especially when the PSU is three months old, and the memory is much older and hasn’t been tested.

bomyne's avatar

If it was a memory problem as you (@flip86) and @BosM suggested, wouldn’t nothing work?

As i said, the system appears to continue it’s normal bootup, just that i have no video or keyboard (It’s a logitech gaming keyboard, which is what i meant by doesn’t light up).

bomyne's avatar

@BhacSsylan I just tried to open the case and i got one of the screws holding the case on, off… but the other screw is too tight and won’t move at all.

Just to clarify what i meant by “long beeps”. The system plays 3 3-second beeps.

BosM's avatar

Apologies for my hasty response this morning as I was in a bit of a rush. I didn’t mean to sound emphatic that a memory issue was the only answer although it is a possible one. Sometimes this is a rule-out process in order to determine root cause.

Check out this link for more information on POST/beep code troubleshooting
http://www.computerhope.com/beep.htm

jerv's avatar

If it was a memory problem as you (@flip86) and @BosM suggested, wouldn’t nothing work?

Not necessarily. I’ve blown a few DIMMS in my day, but the problems were at higher memory addresses, so it didn’t become an issue until the memory filled up to where the problem was.

As Award is a common BIOS, I would lean towards memory issue myself unless/until you specify what BIOS your system actually runs.

@BhacSsylan Have you never had a defective product? Or a cheaply made one that dies really fast? Age doesn’t matter when we are talking about lemons and crap. I would trust 3-year-old Corsair RAM over a 3-month-old no-name PSU.

bomyne's avatar

All that’s managed to do is confuse me further, @BosM. Unfortunately i can’t get the case off to look at the motherboard, but the Phoenix and Award bios sounds familiar.

@Jery One thing i can definitely say is the name of the PSU. Aywun. This is it: http://www.vtechindustries.com.au/550w-aywun-mega-power-pro-series-80plus-bronze-certified-power-supply,-where-the-performance-per-dollar-ratio-is-tuned-up-to-the-maximum-hpc-550-b14s

flip86's avatar

The PSU might not have ruined anything but it may not be powering your system right. I would bet money that the PSU is the main problem.

I bought a cheap PSU for my old Compaq and the thing barely powered it. It wouldn’t run my low end graphics card. The graphics card was for HDMI output. The PSU I bought cost the same as the one you linked.

ARE_you_kidding_me's avatar

The answer is this. Your bios is programmed by just a couple of companies and each have very different beep codes. Your board manual will tell you who supplied the bios. Simply figure out from that who made your bios and look up the beep codes which will tell you where the problem is. Only after that should you listen to anyone on a web forum. Find out and get back with us or post your motherboard model and serial number & I’ll look it up. I guarantee you there is a way to get the case open

flip86's avatar

Use this tool – CPU-Z. It will tell you what everyone wants to know. Nevermind. I forgot you have no video.

BhacSsylan's avatar

@jerv I suppose that’s true, I guess i was reacting more to the ‘mobo might be dead, throw everything away’ bit which, frankly, is still nonsense. But that may possibly be the underlying issue.

However, still need to the codes to see if that’s even what it thinks is wrong.

Lightlyseared's avatar

Really you’re going to have to get the case open. Not only will it make diagnosing the fault easier as you’ll be able to see what components are in there but what ever is wrong its a hardware fault so if you want to try and fix it you need to be able to access the hardware.

jerv's avatar

Aywun? Never heard of them :/ Bad pun an A1. Sounds like they’re trying to sound better than they are.

Regardless, a memory issue wouldn’t take out your video and keyboard. And if you replace the motherboard, it’ll probably happen again. I’m leaning towards the PSU frying your chipset. Otherwise, you’d have keyboard and video long enough to get a POST message and get into BIOS.

ARE_you_kidding_me's avatar

@jerv I doubt it. The bios runs enough to beep out the error code. This is probably fixable.

rexacoracofalipitorius's avatar

First, get that damn case off. Drill out the screws if you have to. Until you get the case open that computer is a paperweight.
Once it’s open, clean out all the junk. At minimum there will be metal shavings in there if you drilled out the screws. Blast the dust, metal, and crap out before proceeding. Ensure there is no conductive crap inside before you power on again!
With the case open, look for the BIOS chip. It will usually have a big sticker or logo printed on it which will say one of AMI (American Megatrends International) AWARD or PHOENIX. If there’s a model number on the chip, note it as well.
Once you have the vendor you can google what the beep codes mean. Here’s some information that might be helpful:

http://www.ami.com/support/doc/AMIBIOS8_Checkpoint_and_Beep_Code_List_PUB.pdf
http://pcsupport.about.com/od/nonworkingcomponent/ht/beepcodestb.htm
http://h10025.www1.hp.com/ewfrf/wc/document?cc=us&lc=en&dlc=en&docname=c02222922

jerv's avatar

@ARE_you_kidding_me The BIOS is fine, but how’s the actual chipset? I’m talking North Bridge here.

bomyne's avatar

Some how we got the video working just now… and the computer had a message in red saying that a previous overclocking attempt has failed and it was restoring default settings. Thing is though, the computer has never been overclocked. I don’t know how to overclock and i wouldn’t anyway because the system is powerful enough to run all my games without it.

Does anyone know how this could have happened?

Related: The Bios boot system shows a MSI logo then a DrMOS logo.

Thanks.

BhacSsylan's avatar

I’ve seen that a few times, actually (and I have an MSI mobo as well). Most annoyingly when I try to hibernate. So it could be a memory error after all, if you found a bad sector and the BIOS freaked out. One way I’ve found to fix that is to actually ‘reset’ the motherboard: unplug completely, open the case, remove the small rechargable battery on the mobo (usually a small flat battery about the size of a quarter), wait a few seconds, and then reassemble everything. Shouldn’t really need to be done, though, you probably should run something like memtest to see if something is off about your memory.

jerv's avatar

@BhacSsylan Slightly simpler way; many motherboards have a reset jumper. But the CR2032 is not rechargeable, and I’ve occasionally seen a dead mobo battery cause BIOS weirdness. Not often, but enough to be considered as a possibility. And guess where overclocking settings are…

bomyne's avatar

If the motherboard battery is the cause of “bios weirdness” and this could have been a result of that weirdness, then replacing that battery should prevent this in the future?

Though that does mean i still have to get that case open.

jerv's avatar

If so, yes. There’s no real telling how long before it’ll go out again; I’ve seen everywhere from 2 to 10 years.

And yes, you do. I often don’t even have mine screwed on; I can slide that left panel back ½” and get inside in 2 seconds. But usually the ones on e=the removable side are fairly loose while the other side is Loc-tited, making it far easier to remove the correct panel than the wrong one. Usually.

ARE_you_kidding_me's avatar

@jerv the bios cannot run without the chipset.

@bomyne yes if you have a battery on your board for bios change it. You can load “failsafe defaults” and that should make it bootable. If you still experience problems try reflashing the bios.

jerv's avatar

@ARE_you_kidding_me The BIOS is upstream of the chipset. During POST, the BIOS identifies other hardware; CPU, video hardware, keyboards, drive controllers, etcetera. Put in car terms, the BIOS is the starter motor, and I could pull out my car’s starter and it (the starter, not the car) will still run. However, it won’t really do anything productive, a working starter motor won’t crank a seized engine.

Of course, it could just be me using the wrong words to describe the picture in my head. Or possibly just different uses of the word “chipset”.

BhacSsylan's avatar

@jerv fair enough, I haven’t had to mess with it enough to know that, though I have had to replace mine, as well. Maybe it’s lithium and I mixed that up?

Anyway, you really should try and get that case open anyway, at the very least to know how to do it for the future. In most cases I’ve seen, looking from the front, the (easily) openable side is on the left, and usually only held in by screws in the very back. Any of that sound right?

ARE_you_kidding_me's avatar

@jerv the bios is simply a set of hard coded instructions. To use your car analogy “the driver ” during boot. The cpu is like the engine and the chipset is like the drive train. The bios cannot even run if the chipset is not working. It would be like a brain trying to run a body with no spinal column. Without the north or south bridge the computer is like a person with a broken neck. BIOS instructions must still be run by the CPU

jerv's avatar

@BhacSsylan Well, some have a rechargeable, though the vast majority I’ve seen use a CR2032 watch battery. Maybe you have different experiences form me though.

@ARE_you_kidding_me I’ve gotten into the BIOS with my CPU socket empty before :/
Got an error code, of course, but I did get it to POST and allow me into the settings.

BhacSsylan's avatar

Actually, I pretty distinctly remember getting a CR2032 the last time I needed to, and from a quick search it is a lithium battery, so i think i just saw ‘lithium’ and thought ‘lithium-ion rechargeable’. Anyway, end result is the same, just a slip on my part. And yeah, the jumper exists, but I find taking out the large shiny thing to be easier than finding that jumper, but that’s personal preference.

ARE_you_kidding_me's avatar

@jerv That would be a first for me, this would mean that there is secondary processing in the chipset which could be the case on some newer models. I’ve not tried it recently. Without the chipset interface POST still cannot work CPU or not because it’s the link to all of the peripherals. That said it’s possible to smoke some chipset functions yet still have an operable but hobbled machine. Many chipset functions are not operational until their drivers are loaded in the OS

Lightlyseared's avatar

@jerv that’s probably a design feature. If the CPU is a newer model than was available when the BIOS was created its often better to update the BIOS before you put the CPU in. Some boards will even allow you to update the BIOS from a USB stick with out the need for anything else attached to the board (apart from the PSU).

Answer this question

Login

or

Join

to answer.

This question is in the General Section. Responses must be helpful and on-topic.

Your answer will be saved while you login or join.

Have a question? Ask Fluther!

What do you know more about?
or
Knowledge Networking @ Fluther