My system boots fine and runs stably, but when I power down I get a noise from my PC speaker that sounds like a siren-style alarm.

Can someone tell me why and how to fix it?

My system is home assembled. The motherboard, CPU and RAM are under warranty as they were recently bought for upgrade. Here’s what I have:

• Windows XP Professional
• AMD Athlon XP2400+
• 256M RAM
• Gigabyte motherboard model GA-7VT600
• nVidia GeForce4 64M display card
• Western Digital 80G 7200 rpm hard drive
• DVD-ROM
• and a set of the usuals (mouse keyboard)

Thanks for any help you can give me.

Richard Stephenson, Mt Druitt, NSW

I’m glad you’ve got that "noisy annoyance" sorted out now, and your system's running as it should!


For the benefit of readers who may be interested, Richard’s ‘problem’ turned out to have a quite simple cause, and he eventually found it himself. But not until we were well underway with efforts to track down the possible cause of the untoward behaviour his system was suffering from. It can sometimes be difficult pin-pointing the source of a problem, and there’s no ‘warranty support’ to fall back on with home built systems. So for the benefit of those amongst our readership who are home-builders or tinkerers, I’ve written our exchange up to illustrate an example of ‘trouble-shooting’ that may just give some hints that provide a bit of insight into the process.

Richard’s initial question was perhaps more an expression of ‘frustration’ than an explanation, and the first step was to seek a bit more detail of his problem to identify clearly just what was happening. Here’s how the initial response to his question was presented to him. It might give some ‘hints’ to anyone trying to decide just how to ‘describe’ their problem!

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Richard,

I’m currently looking at your question, and I’d like you to provide a bit more detail for me if possible.

To start with, I’d like to know more clearly just what you mean when you say "PC speaker". Do you mean the speaker(s) that you have plugged into your computer to have audio for such things as music and games? Or do you mean the tiny system speaker, that’s inside the system case itself, and is designed to signal errors and so on, from your system hardware?

Next, I’d like a bit more detailed description of the noise you are hearing than you’ve so far provided. Is the ‘siren style alarm’ a continuous note? Is it a ‘melody style’ sound such as you’d hear from a siren such as a police or ambulance siren, for example, and change notes as it’s being sounded? Is it a high-pitched ‘squeal’? If the noise has a change in tone or note, is the change distinct, or does it ‘slide’ into a change of pitch, in the way of speaker ‘feedback’? The term ‘siren style alarm’ may be perfectly evident to you there, but it could mean any of a number of things to someone who can’t experience the sound of it, and any further description will help.

Finally, I’d like to be clearer on exactly when the noise is occurring. Could you describe in more detail please, the sequence of events when you ‘power down’, and just when during the process the sound occurs and how long it persists. Describe changes in screen display, noises you hear coming from the system etc., between pressing the ‘Shut Down’ button, and the system actually completing the process. ‘Locating’ the sound a bit more clearly would help.

It may also be relevant if you let me know about any ‘monitoring’ software or hardware you have on your system. The motherboard comes with an "EasyTune" software utility, but do you have anything else? Have you overclocked’ the system at all?

There’s no immediately obvious cause and solution to what’s happening, and further information will help narrow down the possibilities.

Thanks,
Terry

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Richard responded:

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Terry,

Thank you for trying to help.

By PC speaker I meant the internal speaker that connects to the mobo via 2 wires.

The siren noise is best described as a high / low police style sound and seems to be generated by hardware as it only starts after windows exits and the monitor goes black. The mobo is still powered as the power led is still lit and the system turns off only after the siren sounds.

The system is not overclocked. All settings on mobo are auto detect and have not been changed. The only monitoring software installed from Gigabyte CD is the SIV (system information utility) I didn't install Easytune as it has the ability to overclock the system and my wife sometimes likes to play with programs that she is unsure about.

Richard.

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Now we were talking!

That description gives a clear indication of what the noise sounds like, of precisely when it's occurring and where it's coming from, and of what was installed from amongst the provided ‘utilities’ that are relevant to the matter.

The description of the noise sounds very indicative of an ‘overheating alarm’, and it’s obvious that the motherboard is set to default settings in BIOS. The task is to determine just what might trigger the ‘alarm’ to sound during shutdown. A check of the specifications for Richards motherboard and a read through the motherboard manual indicates that his motherboard provides quite a few monitoring and reporting functions that may be relevant. It doesn’t clarify, however, just why that noise is sounding during shut-down. The information provided so far has me suspicious that somehow an alarm for ‘fan-failure’ is being triggered during the shut-down process, but it’s not obvious how or why. Before suggesting BIOS settings to use, it’s a good idea to check for ‘known issues’ that have been resolved with BIOS updates or addressed in Technical support information.

Gigabyte’s motherboard FAQ section contains no issues at all that relate specifically to Richard’s motherboard, and the search function there only allows for searches on motherboard or chipset ID. Frustrating! Their Technical Support Section appears promising right up until the ‘Submit’ button was pressed to send a request for further information, at which time it ‘hung’! Even more frustrating!

Still with no real confirmation of my suspicions, I was preparing to email GigaByte directly, when a message came through from Richard. The initial batch of ‘questions’ had inspired him to perform some ‘lateral thinking’ of his own, and he’d found an answer as a result. Here’s what he said:

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Hi Terry

Thank you again for your willingness to help ,the problem has been found. Siren sound is from a heat sensor being tripped as the CPU fan is not running at its proper speed. The fan has been replaced and the system is now working
correctly.

Richard.

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Great! I’m still not quite sure just why that alarm was sounding when it did, but the noise has gone and Richard’s pleased with that. To be safe, however, there’s a couple of changes I’d advise him to make, as that alarm system doesn’t seem too reliable to me.

Download and install MBM5

Read all the FAQ and support information available on the site to learn how to configure and use the utility. It’s the best heat, voltage and fan speed utility I’ve found, and it has direct support for Richard’s motherboard. What’s more, once you’ve learnt to configure the utility to display just what you want it to report, your wife is going to be quite reluctant to ‘fiddle with it’. It’s not a ‘gimmicky’ display such as the one which characterizes ‘Easytune’, and it’s not as easy to alter. It also doesn’t cater to ‘overclocking’!

MBM5 is a rather tricky tool to come to grips with for starters, but it’s worth persevering with as it gives you easily accessible monitoring reports of the state of health within that system box of yours. The motherboard provides a ‘thermal shutdown’ feature which is supposed to turn the system off if the processor becomes overheated. I’m not sure if that feature is ‘automatic’, as there is no reference to it in the motherboard manual. You should check the ‘Advanced features’ of your BIOS setup to see if there are settings there to enable/disable or to change the values for it. You can access those ‘Advanced features’ by following the instructions on page 32 of your manual.

In any case, it’s better to monitor and detect problems before they reach a critical stage!

After getting MBM5 set up and running on your system, you can disable in BIOS those alarms that are provided, as you’ll no longer need them. Do that by going into BIOS Setup, and on the ‘PC Health Status’ menu, changing the values for "CPU fan fail warning" and "System fan fail warning" to "Disabled". That’s the procedures I use on my own systems, and I’d consider them to be more reliable than the ones that come as stock-standard! Peace of mind, and reliable tools!

Cheers,

Terry O'Shanassy