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Computer off - Activity light on

John January 28, 2009 at 11:38:20
Specs: Windows XP

The computer is shut down, the power light is off. But the activity light flashes periodiclly, and I hear clicking from time to time. Anyone seen this before?

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#1
January 28, 2009 at 19:29:31

It sounds like your computer is in Standby or Hibernate mode. Some hard drives click once, occasionally.
Modern computer ATX mboards are always powered in some places, as long as live AC is being supplied to the power supply on a desktop computer, or as long as the main battery and/or an AC adapter that's powered is plugged in on a laptop, even when the computer is not actively running.

You have not supplied any specific info about your system, or your situation.


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#2
February 14, 2009 at 17:32:09

Thanks for the reply. Sorry it's taken me so long to get back to you on this.

>>It sounds like your computer is in Standby or Hibernate mode

Standby is set to never.
Hibernate is off.
System is fully shut down.

>>You have not supplied any specific info about your system, or your situation.

It's a Soyo P41875P motherboard with an Antec power supply. I have temporarily solved the problem by putting the computer on a power bar and shutting off the power bar once it has finished shutting down. But I would like to debug why it is doing this.


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#3
February 15, 2009 at 08:57:59

Normally, except in rare cases, the only thing that sometimes can make a clicking noise occaisionally is a hard drive that's still spinning.
Depending on which activity led it is, that can be on and flash when the Windows is Shut Down properly - e.g. sometimes leds on network adapters do that - but if it's the hard drive activity led that's doing that, your mboard is definately in Standby or Hibernate mode, whether it should be or not.

It sometimes doesn't matter what your settings in Windows are regarding Standby in Windows are if something else is not right - your computer may go into Standby or Hibernate mode anyway when you attempt to Shut Down Windows.

The most common reason for that is Windows doesn't have the proper info about how the ACPI support of your mboard works, which can determine whether or not Standby, Hibernate, Shut Down, etc. works properly.

Usually that's caused by you or someone who did it for you loading or re-loading Windows from scratch and NOT loading the main chipset drivers, which include the info Windows needs to know about the ACPI support the mboard has.

In the case of Windows XP, it was first released in 2002? and what it can recognize with what is built into it has not changed much since, even with the SPx updates. It is likely that when your mboard is newer than that, it can't find all the info it needs to know about your mboard on it's own.

Whenever you load Windows from a regular Windows CD (or DVD) from scratch, after Setup is finished you must load the drivers for the mboard, particularly the main chipset drivers, in order for Windows to have the proper drivers for and information about your mboard hardware, including it's AGP or PCI-E, ACPI, USB 2.0 if it has it, and hard drive controller support. If you have a generic system and have the CD that came with the mboard, all the necessary drivers are on it. If you load drivers from the web, brand name system builders and mboard makers often DO NOT have the main chipset drivers listed in the downloads for your model - in that case you must go to the maker of the main chipset's web site, get the drivers, and load them.
......

If that's not what caused your problem, other things can cause the computer to not Shut Down properly and go into Standby or Hibernate mode rather than than the mboard shutting off completely.

Probably the most common cause of that is some software you have loaded is causing the problem.

Try this.

Remove any bootable CDs or DVDs you have in drives.

If your computer is actually going into Standby or Hibernate mode instead of shutting off comletely, doing this should make it shut off completely....

Hold the power button in until the mboard shuts off completely - on most ATX computers that takes 4 seconds or more - the activity led and any other leds will go off and stay off, other than possibly one for a network adapter or a mouse which may stay on, and no drive or fan will be spinning. You should hear no clicks - normally, only a hard drive that is still spinning can make that noise.

(Some higher end PSs continue to spin a fan at a slow speed for a short time after you have shut down Windows.
Rarely: some power supplies have been known to make tiny noises after you have shut down Windows, when they still have live AC being supplied to them.)

Repeatedly press F8 while booting, don't hold down the key, starting very early in the boot sequence.
When the boot choices menu appears, select Enable VGA mode.
That loads everything normally, except it forces the video to use default VGA drivers instead of the specific drivers you have loaded for the video.
Once the desktop has loaded, Shut Down Windows.
If doing that shuts the mboard off properly, your problem has something to do with the specific video drivers you normally load when you boot normally.
E.g. a friend of mine's laptop had that problem - I loaded an older video drivers version for his integrated video and the problem disappeared.
Or - the problem may be cured by loading a newer version of them, or drivers from an alternate source.
In his case, I got the older drivers from the Sony site, rather than from the Intel site.

If the mboard still does not shut off properly when you boot into Enable VGA, try booting while repeatedly pressing F8 again, and choose Safe mode from the boot choices menu.
Once the desktop has loaded, Shut Down Windows.

If the mboard then shuts off properly, something that Safe mode does not load that booting normally loads is causing your problem, but it probably has nothing to do with the specific video drivers you load when you boot normally.
......

It can sometimes be caused by a defective power supply, but that's extremely unlikely in your case since you have an Antec PS.
The only way to tell for sure is to try another PS that has enough capacity with your mboard - borrow one from a working system temporarily if you can if you want to try that.


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#4
February 15, 2009 at 15:49:50

Thanks for the swift and thorough reply.

If the MB drivers weren't loaded it's on me, I built it. It's normally the first step I do after loading the OS, but even I can make mistakes ;-) They looked correct in device manager, but I reloaded them from the MB CD just to be sure. (I make a box that contains all the hardware CDs and docs every time I build a new system, so I can always find them easily.)

No joy on that step.

BTW, it did not start doing this right after it was built, it is just recently that this has started.

I'm trying the other steps you suggested, but it isn't 100% reliable on doing this so it may take a bit.

Quick question... If the system is fully powered off, i.e. unplugged from the wall, wait 60 seconds for the capacitors to discharge and then turn it back on. And assuming "Power on after power fail" is set to false, which it is. It should not come up in suspend or hibernate, should it?

I just did the VGA test you mentioned and it shut down OK. I then powered it off waited and turned it back on. The power supply and ACPI light came on and stayed on, but the system did not boot. (It does boot when I hit the power switch)


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#5
February 15, 2009 at 16:58:01

"If the system is fully powered off, i.e. unplugged from the wall, wait 60 seconds for the capacitors to discharge and then turn it back on. And assuming "Power on after power fail" is set to false, which it is. It should not come up in suspend or hibernate, should it?"

I would think it wouldn't come on in suspend or hibernate mode, but I have not tried that. I still have that laptop that had the video driver problem, but it has no lid and no leds other than on the CD drive otherwise, so it would be fruitless to try re-loading the problem video drivers again to try that out

"I just did the VGA test you mentioned and it shut down OK."

Ok then, in you mean booting into Enable VGA mode, your problem is related to the specific video drivers that are loaded in normal mode. Un-install them in Enable VGA mode or normal mode - you may not be able to un-install them in Safe mode.

See response 12 in this for the gist of what you need to do
http://www.computing.net/answers/wi...
- the beginning, and further down starting starting at
"Un-install everything listed in Add/Remove programs for the ATI video"

It's for ATI video drivers, but most of it applies to any video drivers.
You could try re-installing the drivers you installed before, or a newer or an older version, or if you have ATI or NVidia video, the Omega drivers.

" I then powered it off waited and turned it back on. The power supply and ACPI light came on and stayed on, but the system did not boot. (It does boot when I hit the power switch)

If there is an led on the PS, it should be on when the PS switch, if has one, is on, and when that and the AC to the computer/power supply is on. There is often also an led on the surface of the mboard that lights up whenever the PS is receiving live AC, whether the computer is running or not - that led is there to remind you the ATX mboard is always powered in some places as long as the PS is receiving live AC (and the PS is switched on).

Which "ACPI" led?
If you mean on the monitor, that's often one color when it's powered on and is receiving no video signal (e.g. amber) , another color (e.g. green)when you boot the computer or the computer is running and it is receiving a video signal; that second color may come on briefly and change to the first color after a few seconds when the monitor is receiving no video signal.

If you mean on the case front, some cases have an additional led for sleep/standby/hibernate mode, or the power led is a dual led that is one color when the computer is powered on, another when it's in sleep/standby/hibernate mode. I've never had such, so I don't know if the led or the color the dual led for "ACPI" (sleep/standby/hibernate) mode is on when you merely restore the AC power to the case/PS.


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#6
April 9, 2009 at 01:09:07

Hi

I don't know if the problem was solved but i just had the same problem! I shutted down the computer and every light was off! Few hours later, I notices that there was sound coming out of the computer and the activity light was blinking weakly.

I opened the box and saw the fan of my ATI graphic card spinning! I thought there was a problem with my graphic card. I just installed a fresh copy of Windows XP Pro and everytime i turn on my computer, I get the message "A disk read error occured. Press Ctrl-Alt-Del to restart". I brought it to a technician and he said the problem comes from my Power supply. i changed it and everything is fine now! Hope it helps!


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#7
April 9, 2009 at 08:21:59

Antec Guy

Since John Fenton hasn't made another post since Feb 15, I have no idea whether you had thesame problem, but I suspect your problem is only the same as far as something coming on on it's own.

ATX mboards are always powered in some places even when the computer is not running as long as the ATX power supply is getting live AC, and the PS is switched on if it has a switch, and the PS is properly connected to the mboard. The power supply has no ability to turn itself on or turn on anything connected to the mboard, but the mboard's bios does, via default or custom settings in the bios for it's ACPI support . When you use Windows to shut down the computer, Shut Down, Hibernate, and Suspend are three different situations regarding what the ACPI support of the mboard's bios does. E.g. the video card fan may still spin in Suspend mode.

All sorts of situations can cause you to get a message like you got:
"I just installed a fresh copy of Windows XP Pro and everytime i turn on my computer, I get the message "A disk read error occured. Press Ctrl-Alt-Del to restart".

If the power supply is defective and isn't putting out enough of any of the voltages the mboard needs, you may get a message like that, and in that case replacing the power supply would fix the problem, but that isn't necessarily the thing that would cause you to get a message like that.


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