Last night had a power "bump"... AC out for less than 5 seconds, then
back on. This AM, daughter's computer dead. Power supply tester says
Antec Smart Power 500 is good (even the fans not connected to the
motherboard fired up when the tester was connected). No leaking or
bulging caps apparent. Is it possible just the case power switch is bad?
To test it, can I use a jumper to (or screwdriver) to jump across the
"pwr sw" pins? It's an ASUS A8N-E board, and the green LED on the board
does come on, but nothing happens when I press the PWR button on the case.
yes you can jump it just touch it with a piece of metal but first try
unpluging the power supply for a few minutes then plug it back in and see
what happens.
"Fitz" <akfitz@gci.net> wrote in message
news:13bvmibp0itfibf@corp.supernews.com...
> Last night had a power "bump"... AC out for less than 5 seconds, then back
> on. This AM, daughter's computer dead. Power supply tester says Antec
> Smart Power 500 is good (even the fans not connected to the motherboard
> fired up when the tester was connected). No leaking or bulging caps
> apparent. Is it possible just the case power switch is bad? To test it,
> can I use a jumper to (or screwdriver) to jump across the "pwr sw" pins?
> It's an ASUS A8N-E board, and the green LED on the board does come on, but
> nothing happens when I press the PWR button on the case.
>
> Thanks,
>
> Fitz
If you are SURE that the PSU is good, then it sounds like the motherboard
was fried by the surge. (That's why I ALWAYS use an expensive surge
protector to plug my system into. A relatively cheap cost to protect my
greater investment.)
--
---------------------
DaveW
"Fitz" <akfitz@gci.net> wrote in message
news:13bvmibp0itfibf@corp.supernews.com...
> Last night had a power "bump"... AC out for less than 5 seconds, then back
> on. This AM, daughter's computer dead. Power supply tester says Antec
> Smart Power 500 is good (even the fans not connected to the motherboard
> fired up when the tester was connected). No leaking or bulging caps
> apparent. Is it possible just the case power switch is bad? To test it,
> can I use a jumper to (or screwdriver) to jump across the "pwr sw" pins?
> It's an ASUS A8N-E board, and the green LED on the board does come on, but
> nothing happens when I press the PWR button on the case.
>
> Thanks,
>
> Fitz
DaveW wrote:
> If you are SURE that the PSU is good, then it sounds like the motherboard
> was fried by the surge. (That's why I ALWAYS use an expensive surge
> protector to plug my system into. A relatively cheap cost to protect my
> greater investment.)
>
It was on a surge protector, which is somewhat irratating. I've only
investigated the PS to the extent of plugging it in to an Antec PS
tester, which I understand may not be definitive. But it does indicate
that the PS is working, and as I originally posted, the computer fans
that are plugged directly into the PS turn on when the ATX cable is
connected to the tester and turned on.
> DaveW wrote:
>> If you are SURE that the PSU is good, then it sounds like the
>> motherboard was fried by the surge. (That's why I ALWAYS use an
>> expensive surge protector to plug my system into. A relatively
>> cheap cost to protect my greater investment.)
>>
> It was on a surge protector, which is somewhat irratating. I've only
> investigated the PS to the extent of plugging it in to an Antec PS
> tester, which I understand may not be definitive. But it does
> indicate that the PS is working, and as I originally posted, the
> computer fans that are plugged directly into the PS turn on when the
> ATX cable is connected to the tester and turned on.
After you get things worked out.
Consider a voltage regulator (line conditioner). Inexpensive and can
help a lot with power irregularities.
On Aug 14, 4:29 pm, Fitz <akf...@gci.net> wrote:
> It was on asurgeprotector, which is somewhat irratating. I've only
> investigated the PS to the extent of plugging it in to an Antec PS
> tester, which I understand may not be definitive. But it does indicate
> that the PS is working, and as I originally posted, the computer fans
> that are plugged directly into the PS turn on when the ATX cable is
> connected to the tester and turned on.
Numerous assumptions were made that are widely believed and yet are
outright myths. As you noted, defective power supplies can be
reported OK by that power supply tester. To accurately test the power
supply, a tester must apply a load so great that the tester would be
too hot to hold - ie 300 watts. Clearly your power supply tester does
not do that. Defective supplies can appear to work just fine without
a sufficient load. Just another reason why the best power supply test
means leaving the supply connected to computer - not even one
connector change.
A definitive answer means never disconnecting anything; instead
using a 3.5 digit multimeter to get useful numbers in only two
minutes. Some complain they don't have a meter. Not relevant. They
have a screwdriver? A standard tool - the meter - is also sold in
same stores such as K-mart for little money. Why in K-mart? The so
inexpensive tool is for everyone; also sold in Wal-Mart, Lowes, Sears,
Radio Shack, your local hardware store, etc.
Is the suspect a power supply or some other components of the power
supply 'system'? A tester never reported on the power 'system'. Your
problem could be any 'system' component.
Surges can be succeeded by brownouts or dimming. You have assumed a
plug-in protector protects from surges that typically cause damage.
It does not and can even give a surge more destructive paths inside an
adjacent computer. Where do protector's numeric specs claim
protection? It does not. It does protect from a type of surge that
typically does not cause damage. It forgets to mention that an
adjacent protector does not protect from a type of surge that
typically does cause damage. Worse, protectors too close to
electronics and too far from earth ground may simply earth surges,
destructively, through a computer.
Do you know any electrical engineers who literally traced such
damage to a network of powered off computers? This one has. A surge
shunted into two adjacent computers by adjacent surge protectors then
earthed the surge, destructively, via a third powered off computer.
Yes, a protector without a short connection to earth may, instead,
earth surges destructively through an adjacent computer. Does your
protector claim to protect from that type of surge? If so, then it
says so in numbers.
Meanwhile, a surge is only one possible reason for your failure.
Above is how damage could have been created. Next is how to find
that damage before replacing anything - without shotgunning. A two
minute procedure either will identify suspects or confirm power
'system' as functional. Procedure will provide numbers so that
others with greater knowledge can provide additional assistance.
Without numbers, every reply can only be wild speculation.
Now you have numbers. Your replies will only be as good as numbers
you have provided. Information in those numbers may be apparent only
to those with better knowledge.
Most all failures leave no visible indication. Inspection other
than for most obvious problems is mostly useless. Even a power
supply that appears to work on a tester may be 100% defective. Post
those numbers from a multimeter to get definitive answers quickly -
and without shotgunning.
At least one who has already posted here has a history of 'attacking
this messenger' mostly due to technical ignorance and a love of
shotgunning. That poster even asks questions that a first year
engineer should know. Technical knowledge so thin that he
automatically knows he knows. The less some people know, then the
more they insist they know. Ignore those posts that are especially
devoid of numbers and technical grasp to find and eliminate this
problem quickly AND want to learn from the experience.
On Aug 14, 5:08 pm, John Doe <j...@usenetlove.invalid> wrote:
> After you get things worked out.
> Consider a voltage regulator (line conditioner). Inexpensive and can
> help a lot withpowerirregularities.
Eliminating power irregularities is the job of a power supply. If
power supply is missing voltage regulator functions, then power supply
was defective when purchased. Solution: replace the defective supply.
Whereas line conditioning was even standard in 1950s TV and required
in 1970 computer industry standards, then why in 2000+ would a line
conditioner be required?
A power supply contains layer after layer of line conditioning.
Some examples. First power passes through a line filter. Then AC is
converted to 300 volts DC. Then another filter. Then filtered 300
VDC is converted to AC at tens or hundreds of kilohertz. Then
filtered again and converted to low voltage by a transformer. Then it
is filtered again. All this must be in every computer power supply.
All this should be well known to those who make recommendations.
But somehow a power supply needs a line conditioner? Somehow a line
conditioner not as effective as the transformer inside the power
supply will somehow accomplish what the power supply could not?
How much must a line conditioner cost just to supplement what is
already inside that power supply? Hundreds of dollars. Anything less
does nothing.
Why do some recommend line conditioners? Because they saved $10 or
$20 on a power supply that was missing essential functions. Or because
they heard line conditiong is necessary and did not first learn
technology using an oscilloscope. That line conditioner
recommendation is bogus; often found where basic electrical knowledge
is missing. Many who recommend do not even know of the many power
supply functions. One function of computer power supplies as even
demanded over a decade ago by Intel standard: output power is
massively conditioned.
A line conditioner is recommended because it is a 'magic box'. If a
recommendataion was based in technical fact, then the recommendation
would provide numbers that explain why a line conditioner is
necessary. Just another reason why a line conditioner recommendation
is bogus.
> On Aug 14, 5:08 pm, John Doe <j... usenetlove.invalid> wrote:
>> After you get things worked out.
>> Consider a voltage regulator (line conditioner). Inexpensive and
>> can help a lot withpowerirregularities.
<snipped w_tom's strange rant against voltage regulators>
w_tom used to search the archives for "power supply" and "surge
suppressor" just so he could jump in whichever group and spew a bunch
of weirdness against surge suppressors. Maybe the problem occurs when
he doesn't understand something, but he isn't humble enough to ask
about it. He should visit the electronics design group and ask them
for an explanation why a voltage regulator might be useful to a
personal computer. Some of my best reading is their intelligent
replies to w_tom's strange arguments.
Seems w_tom stopped doing the anti surge suppressor crusade after
someone explained that a surge suppressor doesn't have to shunt spikes
to ground, it just acts as a clamp that equals out the voltage at both
ends of the circuit. Apparently that was the information he was
trolling for.
w_tom wrote:
> On Aug 14, 4:29 pm, Fitz <akf...@gci.net> wrote:
>> It was on asurgeprotector, which is somewhat irratating. I've only
>> investigated the PS to the extent of plugging it in to an Antec PS
>> tester, which I understand may not be definitive. But it does indicate
>> that the PS is working, and as I originally posted, the computer fans
>> that are plugged directly into the PS turn on when the ATX cable is
>> connected to the tester and turned on.
>
> Surges can be succeeded by brownouts or dimming. You have assumed a
> plug-in protector protects from surges that typically cause damage.
> It does not and can even give a surge more destructive paths inside an
> adjacent computer.
The best information on surges and surge protection I have seen is at: http://omegaps.com/Lightning%20Guide...ion_May051.pdf
- "How to protect your house and its contents from lightning: IEEE guide
for surge protection of equipment connected to AC power and
communication circuits" published by the IEEE in 2005 (the IEEE is the
dominant organization of electrical and electronic engineers in the US).
And also: http://www.nist.gov/public_affairs/p.../surgesfnl.pdf
- "NIST recommended practice guide: Surges Happen!: how to protect the
appliances in your home" published by the US National Institute of
Standards and Technology in 2001
The IEEE guide is aimed at those with some technical background. The
NIST guide is aimed at the unwashed masses.
Both the IEEE and NIST guides say plug-in suppressors are effective.
Ratings range from junk to very high.
> Where do protector's numeric specs claim
> protection? It does not. It does protect from a type of surge that
> typically does not cause damage.
Complete nonsense. Plug-in suppressors have MOVs from H-N, H-G, N-G.
That is all combinations of power wires and all surge modes. They also
have voltage clamps on signal wires going through the suppressor.
Note that all interconnected equipment needs to be connected to the same
plug-in suppressor, or interconnecting wires need to go through the
suppressor. External connections, like phone, also need to go through
the suppressor. Connecting all wiring through the suppressor prevents
damaging voltages between power and signal wires. These multiport
suppressors are described in both guides.
According to NIST guide, US insurance information indicates equipment
most frequently damaged by lightning is
computers with a modem connection
TVs, VCRs and similar equipment (presumably with cable TV
connections).
All can be damaged by high voltages between power and signal wires.
> Ignore those posts that are especially
> devoid of numbers and technical grasp
For a reliable technical grasp read the IEEE and/or NIST guides.
> Surges can be succeeded by brownouts or dimming. You have assumed
> a plug-in protector protects from surges that typically cause damage.
> It does not and can even give a surge more destructive paths inside
> an adjacent computer.
Well, I thought w_tom got a clue, but apparently not.
Maybe he was connected to a surge suppressor as a baby,
and it didn't work.
> Path: newsdbm02.news.prodigy.net!newsdst02.news.prodigy. net!prodigy.com!newscon02.news.prodigy.net!prodigy .net!border1.nntp.dca.giganews.com!nntp.giganews.c om!postnews.google.com!r34g2000hsd.googlegroups.co m!not-for-mail
> From: w_tom <w_tom1 usa.net>
> Newsgroups: alt.comp.hardware.pc-homebuilt
> Subject: Re: AC power bump, dead computer
> Date: Tue, 14 Aug 2007 16:50:05 -0700
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> On Aug 14, 4:29 pm, Fitz <akf... gci.net> wrote:
>> It was on asurgeprotector, which is somewhat irratating. I've only
>> investigated the PS to the extent of plugging it in to an Antec PS
>> tester, which I understand may not be definitive. But it does indicate
>> that the PS is working, and as I originally posted, the computer fans
>> that are plugged directly into the PS turn on when the ATX cable is
>> connected to the tester and turned on.
>
> Numerous assumptions were made that are widely believed and yet are
> outright myths. As you noted, defective power supplies can be
> reported OK by that power supply tester. To accurately test the power
> supply, a tester must apply a load so great that the tester would be
> too hot to hold - ie 300 watts. Clearly your power supply tester does
> not do that. Defective supplies can appear to work just fine without
> a sufficient load. Just another reason why the best power supply test
> means leaving the supply connected to computer - not even one
> connector change.
>
> A definitive answer means never disconnecting anything; instead
> using a 3.5 digit multimeter to get useful numbers in only two
> minutes. Some complain they don't have a meter. Not relevant. They
> have a screwdriver? A standard tool - the meter - is also sold in
> same stores such as K-mart for little money. Why in K-mart? The so
> inexpensive tool is for everyone; also sold in Wal-Mart, Lowes, Sears,
> Radio Shack, your local hardware store, etc.
>
> Is the suspect a power supply or some other components of the power
> supply 'system'? A tester never reported on the power 'system'. Your
> problem could be any 'system' component.
>
> Surges can be succeeded by brownouts or dimming. You have assumed a
> plug-in protector protects from surges that typically cause damage.
> It does not and can even give a surge more destructive paths inside an
> adjacent computer. Where do protector's numeric specs claim
> protection? It does not. It does protect from a type of surge that
> typically does not cause damage. It forgets to mention that an
> adjacent protector does not protect from a type of surge that
> typically does cause damage. Worse, protectors too close to
> electronics and too far from earth ground may simply earth surges,
> destructively, through a computer.
>
> Do you know any electrical engineers who literally traced such
> damage to a network of powered off computers? This one has. A surge
> shunted into two adjacent computers by adjacent surge protectors then
> earthed the surge, destructively, via a third powered off computer.
> Yes, a protector without a short connection to earth may, instead,
> earth surges destructively through an adjacent computer. Does your
> protector claim to protect from that type of surge? If so, then it
> says so in numbers.
>
> Meanwhile, a surge is only one possible reason for your failure.
>
> Above is how damage could have been created. Next is how to find
> that damage before replacing anything - without shotgunning. A two
> minute procedure either will identify suspects or confirm power
> 'system' as functional. Procedure will provide numbers so that
> others with greater knowledge can provide additional assistance.
> Without numbers, every reply can only be wild speculation.
>
> Two minute procedure is in "When your computer dies without
> warning....." starting 6 Feb 2007 in the newsgroup alt.windows-xp
> at:
> http://tinyurl.com/yvf9vh
> Pictures (not associated text) to help understand that procedure:
> http://techrepublic.com.com/5102-10586-5566528.html
> http://www.helpwithpcs.com/courses/p...nc-pinouts.htm
>
> Now you have numbers. Your replies will only be as good as numbers
> you have provided. Information in those numbers may be apparent only
> to those with better knowledge.
>
> Most all failures leave no visible indication. Inspection other
> than for most obvious problems is mostly useless. Even a power
> supply that appears to work on a tester may be 100% defective. Post
> those numbers from a multimeter to get definitive answers quickly -
> and without shotgunning.
>
> At least one who has already posted here has a history of 'attacking
> this messenger' mostly due to technical ignorance and a love of
> shotgunning. That poster even asks questions that a first year
> engineer should know. Technical knowledge so thin that he
> automatically knows he knows. The less some people know, then the
> more they insist they know. Ignore those posts that are especially
> devoid of numbers and technical grasp to find and eliminate this
> problem quickly AND want to learn from the experience.
>
>
AC power bump, dead computer 
Linear Mode
