Computer Randomly Powers Off

[Paige Miller]

My computer has randomly powered itself off a few times. I do not mean
it crashes or freezes or there is the blue screen of death. I mean
that I am using the computer and then instantaneously it appears to
have no power -- all lights on the case go off -- and must be
restarted, despite the fact that I have a surge protector and that
other devices (such as the monitor and speakers) plugged into the same
surge protector have not lost power.

The common thread in all of this is that it happens when I am
listening to some sort of sounds from the computer. This could be
watching a video, listening to internet radio, or playing games. This
has happened in several pieces of software, including my web browser,
RealPlayer and game software. Today, I was listening to ESPN Radio
through my computer for about 20 minutes when it powered off.

So, how do I diagnose this further? It seems like it must be a
hardware problem. Is it the power supply or the sound card or the
mother board or all of the above or something else? What should I do
next?

--
Paige Miller
(e-mail address removed)

It's nothing until I call it -- Bill Klem, NL Umpire
If you get the choice to sit it out or dance,
I hope you dance -- Lee Ann Womack

 

[Paul]

My computer has randomly powered itself off a few times. I do not mean
it crashes or freezes or there is the blue screen of death. I mean that
I am using the computer and then instantaneously it appears to have no
power -- all lights on the case go off -- and must be restarted, despite
the fact that I have a surge protector and that other devices (such as
the monitor and speakers) plugged into the same surge protector have not
lost power.

The common thread in all of this is that it happens when I am listening
to some sort of sounds from the computer. This could be watching a
video, listening to internet radio, or playing games. This has happened
in several pieces of software, including my web browser, RealPlayer and
game software. Today, I was listening to ESPN Radio through my computer
for about 20 minutes when it powered off.

So, how do I diagnose this further? It seems like it must be a hardware
problem. Is it the power supply or the sound card or the mother board or
all of the above or something else? What should I do next?

One switch-off mechanism, on modern motherboards, is CPU overheat.
A diode inside the processor is used to sense its temperature, and
if the CPU gets hot enough, it sends a signal called THERMTRIP to
the motherboard logic. That in turn, is used to turn off the power
supply. So you might check and see whether the processor is getting
hot - some computers come with a monitoring program, that tells
you the processor temperature. If the CPU is getting too hot,
then you remove the heatsink from the CPU, and apply fresh thermal
paste to the interface between the CPU and the heatsink. Once the
heat is able to flow into the heatsink again, the CPU will stop
overheating.

A second shutdown mechanism, is an overload on +5VSB. That particular
signal, is normally used to power certain parts of the computer, when
the computer is "suspended to RAM", A.K.A "asleep". If there is a
momentary loss of power on that rail, the computer will switch off.
On some computers, it is possible for the user to place too much
load on that signal. One way that happens, is if you use a lot of
high power USB devices, and the motherboard is configured to power
the USB ports from +5VSB. (If you have an optical mouse, and the
mouse has a red LED, and the LED is lit while the computer sleeps,
then the USB ports are powered by +5VSB.) It would take four Alcatel
"Frog" DSL modems, to overload a power supply. Or maybe four USB
scanners, all scanning at the same time. But this isn't likely to be
the problem.

If you want more hints, perhaps you could describe the machine in
more detail, what power supply it has got, what toys are plugged into
it, and so on. The more details you give, the more theories we can give.

Also, another important thing to observe - is it difficult to start the
computer, right after it switches off ? Do you have to unplug it, to
get it to recover. Does it start as soon as you push the button on
the case ? That information is also useful, when formulating a theory
as to why.

Paul

 

[Guest]

Make sure all cooling fans are working and free of dust bunnies, may be over
heating problem.. The PSU, could also be the culprit too, if so it may be a
good idea to put it in the shop, for an accurate assessment..
Cheers
j;-j

 

[Paige Miller]

One switch-off mechanism, on modern motherboards, is CPU overheat.
A diode inside the processor is used to sense its temperature, and
if the CPU gets hot enough, it sends a signal called THERMTRIP to
the motherboard logic. That in turn, is used to turn off the power
supply. So you might check and see whether the processor is getting
hot - some computers come with a monitoring program, that tells
you the processor temperature. If the CPU is getting too hot,
then you remove the heatsink from the CPU, and apply fresh thermal
paste to the interface between the CPU and the heatsink. Once the
heat is able to flow into the heatsink again, the CPU will stop
overheating.

Thanks, I will check the CPU and see if it is getting too hot. Could
it also be the fan is not operating properly?

Why would playing audio through the speakers be correlated with these
power off-episodes? Random coincidence?

A second shutdown mechanism, is an overload on +5VSB. That particular
signal, is normally used to power certain parts of the computer, when
the computer is "suspended to RAM", A.K.A "asleep". If there is a
momentary loss of power on that rail, the computer will switch off.
On some computers, it is possible for the user to place too much
load on that signal. One way that happens, is if you use a lot of
high power USB devices, and the motherboard is configured to power
the USB ports from +5VSB. (If you have an optical mouse, and the
mouse has a red LED, and the LED is lit while the computer sleeps,
then the USB ports are powered by +5VSB.) It would take four Alcatel
"Frog" DSL modems, to overload a power supply. Or maybe four USB
scanners, all scanning at the same time. But this isn't likely to be
the problem.

Usually, I have zero USB devices plugged in and drawing power. The
printer is plugged into a USB port, but the printer is usually
switched off. Occasionally, but not when the problem occurs, I have a
camera or MP3 player plugged into a USB port. The keyboard and mouse
are not USB devices.

If you want more hints, perhaps you could describe the machine in
more detail, what power supply it has got, what toys are plugged into
it, and so on. The more details you give, the more theories we can give.

My configuration is:
OEM AMD ATHLON 64 3500+CPU 939 PIN
HITACHI 80GB SATA150 7200 RPM HD
WD 160GB 7200RPM ATA 100 8MB
512MB PC3200 PC400 DDR
CASE FAN
COOLERMASTER AMD ATHLON 64 3700+FAN
BEIGE SONY 16X DVDRW DW-Q28A DUAL
SONY 16X DVD EDIE
6-IN-ONE MEDIA READER BIEGE
SONY FLOPPY DRIVE 1.44 MB
LOGITECH DELUXE 104 KEYBOARD BEIGE
LOGITECH OPTICAL WHEEL MOUSE
MSI K8N NEO4-F NF4 PCI-E
NETWORK CARD PCI 10/100
CREATIVE SB LIVE! 24BIT 7.1 VARPAK
LOGITECH X530 5.1 SPEAKER
XFX 6200 TURBOCACHE SUPPORTING 256M

The power supply was not listed on the invoice, so I cannot say what
kind of power supply it is. But I have had this computer for over a
year, and the problem just began this week.

Also, another important thing to observe - is it difficult to start the
computer, right after it switches off ? Do you have to unplug it, to
get it to recover. Does it start as soon as you push the button on
the case ? That information is also useful, when formulating a theory
as to why.

It usually restarts without problem. Once or twice when it restarted
and Windows played the startup sound, it did the spontaneous turn-off,
and the next restart everything was fine.


--
Paige Miller
(e-mail address removed)

It's nothing until I call it -- Bill Klem, NL Umpire
If you get the choice to sit it out or dance,
I hope you dance -- Lee Ann Womack

 

[w_tom]

If heat created shutdown in a 70 degree room, then heat is a
diagnostic tool to find the 100% defective hardware component. A
component that is getting worse with age. That computer must work just
fine even in a 100 degree F room. Dust bunnies would not explain this
shutdown. CPU must get 30 degrees warmer and still not overheat. If
heat in a 70 degree room causes a shutdown, then computer has a
completely defective hardware item. Use more heat to find that
defective part. Also use comprehensive hardware diagnostics in
combination with a hairdryer on high heat to find that defective
hardware.

Heat is rarely a reason for this type failure if CPU fan is spinning.
Mentioned was overloading in the +5VSB. However if that +5VSB was
overloaded and creating a shutdown today, then this following test
would have identified that failure even a year ago. An overloaded
voltage is detectable by a meter long before overloading creates a
shutdown. A 3.5 digit multimeter measuring voltage on purple, red,
orange, and yellow wire (from power supply to motherboard) will report
overloading or will eliminate the power supply as a suspect. Meter
readings taken when multiple peripherals are being accessed
simultaneously is the only way of getting a definitive answer. Those
voltages must be greater than 3.23, 4.87, and 11.7.

Immediate shutdowns created by the system may be recorded in the
system (event) logs. Find events (and Device Manager information) in
Control Panel or use Windows Help to get that information. For
example, problems that may have been occurring for the past six months
and have now created unexpected shutdowns might be recorded in those
logs.

Why would use of speakers correlate with power off-episodes? An
overloaded power supply voltage might be loaded just enough to finally
trip out the Power Good detector circuit. But again, this would be
made obvious or would be eliminated by numbers from a digital meter.

USB devices draw near zero power - would hardly be sufficient to trip
out Power Good. Printer powered on or off would be irrelevant. If any
of these could explain the shutdown, then that undersized power supply
would have always been identified by that meter.

 

[Paul]

Thanks, I will check the CPU and see if it is getting too hot. Could it
also be the fan is not operating properly?

Why would playing audio through the speakers be correlated with these
power off-episodes? Random coincidence?


Usually, I have zero USB devices plugged in and drawing power. The
printer is plugged into a USB port, but the printer is usually switched
off. Occasionally, but not when the problem occurs, I have a camera or
MP3 player plugged into a USB port. The keyboard and mouse are not USB
devices.

My configuration is:
OEM AMD ATHLON 64 3500+CPU 939 PIN
HITACHI 80GB SATA150 7200 RPM HD
WD 160GB 7200RPM ATA 100 8MB
512MB PC3200 PC400 DDR
CASE FAN
COOLERMASTER AMD ATHLON 64 3700+FAN
BEIGE SONY 16X DVDRW DW-Q28A DUAL
SONY 16X DVD EDIE
6-IN-ONE MEDIA READER BIEGE
SONY FLOPPY DRIVE 1.44 MB
LOGITECH DELUXE 104 KEYBOARD BEIGE
LOGITECH OPTICAL WHEEL MOUSE
MSI K8N NEO4-F NF4 PCI-E
NETWORK CARD PCI 10/100
CREATIVE SB LIVE! 24BIT 7.1 VARPAK
LOGITECH X530 5.1 SPEAKER
XFX 6200 TURBOCACHE SUPPORTING 256M

The power supply was not listed on the invoice, so I cannot say what
kind of power supply it is. But I have had this computer for over a
year, and the problem just began this week.


It usually restarts without problem. Once or twice when it restarted and
Windows played the startup sound, it did the spontaneous turn-off, and
the next restart everything was fine.

http://www.msicomputer.com/product/p_spec.asp?model=K8N_Neo4-F&class=mb

I think I can see a couple of experiments to try. My hypothesis now is,
it is driver related.

1) Uninstall Creative sound driver package from Add/Remove.
Shutdown and pull Creative sound card. (Always unplug the
computer before adding or removing hardware. Avoids surprises.)
Power up, enter BIOS and check that AC'97 sound is enabled.
Save and Exit the BIOS, if you made changes.
Install sound driver for onboard AC'97 sound system.
Plug speakers into the green motherboard audio connector.
Start playing sounds. Does it power off ?

(Realtek ALC driver)
http://www.msi.com.tw/program/support/download/dld/spt_dld_detail.php?UID=727&kind=1

2) Remove AC'97 sound package from (1), via Add/Remove.
Reboot. Enter BIOS and disable AC'97 sound in the BIOS.
Save and Exit. Shutdown.
Reinstall Creative audio card. Make a note of the model number
on the card, maybe something like CTxxxx. You'll need the model
number, when you go to the Creative site, to get the latest
driver. VARPAK probably means the sound card was an OEM version,
which would be a soundcard alone without fancy packaging. Try
installing the latest Creative driver for your card.
Start playing sounds. Does it power off ?

If you are up for a little more work, you could download a copy of
Knoppix (a Live CD distro of Linux). It would be a 700MB download
from Knopper.net (from a mirror site most likely). You burn a CD
from the downloaded .iso file. 700MB is a pretty big image, and
I had to get a different CD burner, the first time I burned one.
Basically, you'd be testing sound playback in an alternate OS,
leaving the Creative card in place. If the system stays powered,
then you would suspect a software problem of some sort. I'll have
to boot into Knoppix now, to see how easy this would be (I use
Knoppix for testing, and not usually to do work.)

HTH,
Paul

 

[Paul]

If you are up for a little more work, you could download a copy of
Knoppix (a Live CD distro of Linux). It would be a 700MB download
from Knopper.net (from a mirror site most likely). You burn a CD
from the downloaded .iso file. 700MB is a pretty big image, and
I had to get a different CD burner, the first time I burned one.
Basically, you'd be testing sound playback in an alternate OS,
leaving the Creative card in place. If the system stays powered,
then you would suspect a software problem of some sort. I'll have
to boot into Knoppix now, to see how easy this would be (I use
Knoppix for testing, and not usually to do work.)

HTH,
Paul

OK. I'm in Knoppix test world.

To boot Knoppix, insert the CD and boot the computer. As long as
the CD is in the BIOS search order, it should get picked up.

At the boot prompt, type "knoppix screen=1280x1024" to get the
desktop to appear at the native resolution of your monitor.

The Knoppix sound system should be working by default. You should
hear (very faint) "initiating startup sequence" when Knoppix boots.

To test, I clicked the Firefox browser button at the bottom of the
screen, used the altavista search engine, and searched on "MP3
test file". I downloaded a file from here, as one of the first
returned links. This is apparently a voice clip, recorded at
low bit rate.

http://www.archive.org/download/testmp3testfile/mpthreetest.mp3

Firefox leaves the download on the deskop.

Double-click on the icon. The XMMS player should appear. Place
your mouse over the XMMS window. Press the up-arrow key
repeatedly. The blue side-scroll window should eventually say
"Volume 100%" or something similar. Now click the play button.
You may need to turn up your computer speakers, to hear the clip.
(I still haven't figured out why the output is not very loud.
There is presumably a second slider, somewhere, that controls final
output volume.)

If the hard drive in the computer is FAT32 (not likely), you may be
able to click the hard drive icon and get files off your drive.
Otherwise, it may be easier to connect to a share on one of your
other computers, and bring a file over that way.

If you have 1GB of RAM in the computer, you can boot the Knoppix
CD with this, at the boot prompt. This copies the entire boot CD
into system RAM, and should allow the CD to be popped out of the
tray. That would allow you to insert a CD with MP3 files on it,
for testing in the Knoppix environment.

knoppix toram screen=1280x1024

Note, when you shutdown Knoppix (logout, via the lower left menu),
remember to turn down your speakers The sound sample they
play at shutdown, seems to be a lot louder than while using XMMS
player. (If I actually understood how sound worked in this environment,
I'd be dangerous...) You will be prompted to remove the boot CD
from the tray, once shutdown is complete. Don't close the door
on your computer, because when you "logout", the CD tray will
eject the boot CD. Of course, if you did the "toram" option,
there would be no CD to eject at shutdown (because you would have
likely removed it earlier). Unix environments disable the tray eject
button, when the file system is busy. So logout is the way to get
your boot CD back, if you booted and were running from it.

Anyway, as I said, it is a bit of extra work, to test with an
alternate OS. So you may want to stick with Windows testing
for now.

Paul

 

[Ben]

Uh oh
Sounds possibly like a CPU problem....
DONT RUN YOUR COMPUTER!!!
The CPU could melt when it is overheated!!!!!!!!!!
Get it serviced ASAP

 

[Guest]

--
Onward through the fog

One switch-off mechanism, on modern motherboards, is CPU overheat.
A diode inside the processor is used to sense its temperature, and
if the CPU gets hot enough, it sends a signal called THERMTRIP to
the motherboard logic. That in turn, is used to turn off the power
supply. So you might check and see whether the processor is getting
hot - some computers come with a monitoring program, that tells
you the processor temperature. If the CPU is getting too hot,
then you remove the heatsink from the CPU, and apply fresh thermal
paste to the interface between the CPU and the heatsink. Once the
heat is able to flow into the heatsink again, the CPU will stop
overheating.

A second shutdown mechanism, is an overload on +5VSB. That particular
signal, is normally used to power certain parts of the computer, when
the computer is "suspended to RAM", A.K.A "asleep". If there is a
momentary loss of power on that rail, the computer will switch off.
On some computers, it is possible for the user to place too much
load on that signal. One way that happens, is if you use a lot of
high power USB devices, and the motherboard is configured to power
the USB ports from +5VSB. (If you have an optical mouse, and the
mouse has a red LED, and the LED is lit while the computer sleeps,
then the USB ports are powered by +5VSB.) It would take four Alcatel
"Frog" DSL modems, to overload a power supply. Or maybe four USB
scanners, all scanning at the same time. But this isn't likely to be
the problem.

If you want more hints, perhaps you could describe the machine in
more detail, what power supply it has got, what toys are plugged into
it, and so on. The more details you give, the more theories we can give.

Also, another important thing to observe - is it difficult to start the
computer, right after it switches off ? Do you have to unplug it, to
get it to recover. Does it start as soon as you push the button on
the case ? That information is also useful, when formulating a theory
as to why.

Paul
Paul I am having a similar power off problem (see my thread Computer powers off randomly). I do have to shut off the power supply switch and wait awhile for the computer to start. What is the significance of this?