Worm, trojan, virus, or simply power supply failure?

[PRNole]

Yesterday, my wife's 5 year-old HP desktop began to re-boot at random
intervals. Sometimes the re-boot occurred after loading the desktop,
other times when attempting to run an application from the desktop,
other times while acquiring the desktop, etc. Sometimes it even re-
boots during the actual boot sequence, shutting down (and/or
rebooting) before loading the desktop.

When allowed sufficient time to do so before re-booting, I have run
both installed antivirus programs and on-line antivirus checks. No
findings.

I have checked all connections and not found any to be loose.

I have checked for out-of-date drivers and all are current.

Just this morning, I decided to re-boot to the bios setup menu
(pressing <Esc> key) just to see if it would also re-boot or not. I
pulled up the setup menu and decided to let it stay on as long as
needed to see what would happen. Shortly after pulling up the menu, it
re-booted again, right from the bios setup menu.

Now, iss this still a sign that a virus may be at work or does it
sound like the power supply may be faulty?

..

 

[Don Phillipson]

Yesterday, my wife's 5 year-old HP desktop began to re-boot at random
intervals. . . .
I have checked all connections and not found any to be loose.
. . .
Now, iss this still a sign that a virus may be at work or does it
sound like the power supply may be faulty?

Likeliest causes are:
1. Failing power supply unit (testable only in a PC repair shop.)
Power supply modules are cheap (and usually installed free.)
2. Overheating: you can test for this at home by removing
one side of the case, to see whether this reduces frequency
of spontaneous reboots.

 

[Peter Foldes]

Sounds like and it is the Power supply. You made it clear by posting the following

When allowed sufficient time to do so before re-booting,<

That means if it cools then it will work. If it is heated up it will shut down

 

[Bob Willard]

Yesterday, my wife's 5 year-old HP desktop began to re-boot at random
intervals. Sometimes the re-boot occurred after loading the desktop,
other times when attempting to run an application from the desktop,
other times while acquiring the desktop, etc. Sometimes it even re-
boots during the actual boot sequence, shutting down (and/or
rebooting) before loading the desktop.

When allowed sufficient time to do so before re-booting, I have run
both installed antivirus programs and on-line antivirus checks. No
findings.

I have checked all connections and not found any to be loose.

I have checked for out-of-date drivers and all are current.

Just this morning, I decided to re-boot to the bios setup menu
(pressing <Esc> key) just to see if it would also re-boot or not. I
pulled up the setup menu and decided to let it stay on as long as
needed to see what would happen. Shortly after pulling up the menu, it
re-booted again, right from the bios setup menu.

Now, iss this still a sign that a virus may be at work or does it
sound like the power supply may be faulty?

.

Sounds like heat buildup. How long has it been since you last cleaned
the filters and fans, and blew the crud out between the fins of the
heatsinks?

 

[PRNole]

Likeliest causes are:
1.  Failing power supply unit (testable only in a PC repair shop.)
Power supply modules are cheap (and usually installed free.)
2.  Overheating:  you can test for this at home by removing
one side of the case, to see whether this reduces frequency
of spontaneous reboots.

Well, I did run it for a while with one of the side panels off and had
the same results. I also blew off all the gunk with a compressed air
can and found it didn't help either. I guess that leaves the power
supply as the probable cause.

Thanks for the info and help.

 

[Paul]

Yesterday, my wife's 5 year-old HP desktop began to re-boot at random
intervals. Sometimes the re-boot occurred after loading the desktop,
other times when attempting to run an application from the desktop,
other times while acquiring the desktop, etc. Sometimes it even re-
boots during the actual boot sequence, shutting down (and/or
rebooting) before loading the desktop.

When allowed sufficient time to do so before re-booting, I have run
both installed antivirus programs and on-line antivirus checks. No
findings.

I have checked all connections and not found any to be loose.

I have checked for out-of-date drivers and all are current.

Just this morning, I decided to re-boot to the bios setup menu
(pressing <Esc> key) just to see if it would also re-boot or not. I
pulled up the setup menu and decided to let it stay on as long as
needed to see what would happen. Shortly after pulling up the menu, it
re-booted again, right from the bios setup menu.

Now, iss this still a sign that a virus may be at work or does it
sound like the power supply may be faulty?

.

Check for leaking capacitors around the processor area.
The problem could be with the motherboard, and you might take
a look near the processor, for stuff like this. Leaking caps
can also leave a brown stain, of dried liquid, underneath the
cap.

http://www.badcaps.net/images/caps/kt7/image004.png

The same problem can afflict the inside of the power supply,
but going in there is not recommended.

Paul

 

[w_tom]

Well, I did run it for a while with one of the side panels off and had
the same results. I also blew off all the gunk with a compressed air
can and found it didn't help either. I guess that leaves thepowersupply
as the probable cause.

Your logic is that once all other possibilities are eliminated, then
the only remaining possibility must be the problem. Sorry. Others
posted only what they understand - a woefully incomplete list. Many
understand heat - not electricity - and posted accordingly.

First collect facts. For example, what do system (event) logs
report? Does Device Manager report any hardware failures or
conflicts? It is an HP. Therefore a responsible computer
manufacturer provided comprehensive hardware diagnostics - for free.
Diagnostics execute without Windows that complicates testing. What do
those hardware diagnostics report?

Power supply may have been defective for months. Defective power
supplies can still boot a computer. But voltage numbers using a 3.5
digit multimeter could have discovered a problem then, AND determined
if the power supply 'system' is defective now. System? Yes, power
system is more than just a power supply which others often do not
know. Which system component is defective OR can you say without
doubt that all system components are good? Needed are definitive
answers such as numbers provided by "When your computer dies without
warning....." starting 6 Feb 2007 in the newsgroup alt.windows-xp
at:
http://tinyurl.com/yvf9vh
Connector chart to locate each color:
http://www.hardwarebook.net/connector/power/atxpower.html

Either numbers obtained in less than 2 minutes will identify the
problem; provide useful replies from the few who actually know how
hardware works; or exonerate the entire power supply 'system' so that
you can move on to other suspects. Move on without using wild
speculation.

Paul has also noted another reason for system instability. Any
bulging on capacitors (especially near the CPU) is an indication of a
pending hardware failure.

If dust was a problem with a computer in a 70 degree room, then the
computer has been defective for a long time. Computers must work just
fine even in a 100 degree room. Executing comprehensive hardware
diagnostics while computer is in a 100 degree room is another way to
find the current failure OR locate impending failures.

Even a defect in the video processing system could cause your
failure. Those who wildly speculate did not even know that? Well,
many will reply. But only a few really demand facts to provide
definitive answers. Posted are how to post useful facts (especially
numbers) so that following replies are useful.

Once hardware is exonerated, then move on to other software
suspects. Provides is how to get definitive answers - not
speculation.

 

[Bruce Chambers]

Snipped..... Dust causes a loss of cooling that could be a
problem in a 5 Deg change, or even an operational change, without any
DEFECT being there. Hardware overheats all the time in systems that are
filthy, fans that have failed, but it's not a defective computer, it's a
defect in cooling.

I'd have to second this assessment. Even the interior of a dust-free
computer, with all of its fans working, is going to be generally running
roughly 40° F (22°) warmer than the ambient room temperature. This puts
it close to the maximum operating temperatures of many of the internal
components.

Additionally, dust makes an excellent insulator, and can cause
localized thermal problems for individual components (particularly
motherboard chips and RAM) without there being any defect originally
inherent in said components. Having said that, though, extended periods
(weeks to months) of even mild over-heating can cause those components
to become defective.


--

Bruce Chambers

Help us help you:


http://support.microsoft.com/default.aspx/kb/555375

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safety deserve neither liberty nor safety. ~Benjamin Franklin

Many people would rather die than think; in fact, most do. ~Bertrand Russell

The philosopher has never killed any priests, whereas the priest has
killed a great many philosophers.
~ Denis Diderot

 

[w_tom]

I'd have to second this assessment. Even the interior of a dust-free
computer, with all of its fans working, is going to be generally running
roughly 40° F (22°) warmer than the ambient room temperature. This puts
it close to the maximum operating temperatures of many of the internal
components.

Now continue with the numbers. A properly constructed computer
works just fine with dust balls when in a 100 degree F room. As long
as dust does not completely obstruct air holes, then the computer
should work just fine.

Leythos again misdirects to create flame wars. The OP has removed
dust and still has the same failure. Dust obviously was not reason
for his problems. Again, wild speculation did not identify the
problem.

Heat is also a diagnostic tool to find defective hardware before
that defect causes failure. Testing a computer in a 100 degree F room
will temporarily make that intermittent into a hard problem - making
the problem easy to locate and correct. Using heat as a diagnostic
tool is also not popular because so many don't appreciate how
semiconductors work.

Listed are reasons for failure and how to find them. Almost none were
listed by others who only understand heat and shotgunning - replacing
parts only on speculation. Heat is the most often blamed reason for
computer failure only because things such as how electricity works are
mysterious for people such as Leythos. And again, Leythos posted no
assistance for the OP; posted only to create a flame war. Computer
with dust balls must work just fine and happy even in a 100 degree F
room.

Heat obviously is not a reason for the OP's problem. Heat can be a
diagnostic tool especially if used with those other posted tools and
procedures.

 

[PRNole]

  Your logic is that once all other possibilities are eliminated, then
the only remaining possibility must be the problem.  Sorry.  Others
posted only what they understand - a woefully incomplete list.  Many
understand heat - not electricity - and posted accordingly.

Well, you're right about not considering all the possibilities and
people only posting what they understand. To allow for this
eventuality, I have cross-posted this on <sci.geo.meteorology> to see
if current weather conditions (I live in South Fla) might contribute
to the problem, <sci.astro> and <sci.physics> to rule out any astral
or interstellar factors, <alt.sci.physics.acoustics> in case its a
localized problem with ambient noise, and other usenet groups too
numerous to include, lest the ones I inadvertently leave out become
offended by my ommission

  First collect facts.  For example, what do system (event) logs
report? Does Device Manager report any hardware failures or
conflicts?  It is an HP.  Therefore a responsible computer
manufacturer provided comprehensive hardware diagnostics - for free.
Diagnostics execute without Windows that complicates testing.  What do
those hardware diagnostics report?

No system event logs, error messages, or other reports have ever been
generated, especially when the PC reboots fromthe bios setup menu.
None. Zilch. Nada.

  Power supply may have been defective for months.  Defective power
supplies can still boot a computer.  But voltage numbers using a 3.5
digit multimeter could have discovered a problem then, AND determined
if the power supply 'system' is defective now.  System?  Yes, power
system is more than just a power supply which others often do not
know.  Which system component is defective OR can you say without
doubt that all system components are good?  Needed are definitive
answers such as numbers provided by "When your computer dies without
warning....."  starting 6 Feb 2007 in the newsgroup  alt.windows-xp
at:
 http://tinyurl.com/yvf9vh
Connector chart to locate each color:
 http://www.hardwarebook.net/connector/power/atxpower.html

I'll get back to you when I follow up and accomplish this suggestion.

  Paul has also noted another reason for system instability.  Any
bulging on capacitors (especially near the CPU) is an indication of a
pending hardware failure.

 If dust was a problem with a computer in a 70 degree room, then the
computer has been defective for a long time.  Computers must work just
fine even in a 100 degree room.  Executing comprehensive hardware
diagnostics while computer is in a 100 degree room is another way to
find the current failure OR locate impending failures.

As I stated earlier, I just about emptied an entire can of compressed
air on all moving blades, fins, grills, filters, and any other part I
found inside the PC case. No effect. BTW, my PC is located in a room
that manages to stay at 73 degrees.

  Even a defect in the video processing system could cause your
failure.  Those who wildly speculate did not even know that?  Well,
many will reply.  But only a few really demand facts to provide
definitive answers.  Posted are how to post useful facts (especially
numbers) so that following replies are useful.

I check this nsg daily to see when others reply and what they suggest.

  Once hardware is exonerated, then move on to other software
suspects.  Provides is how to get definitive answers - not
speculation.

I agree, except I worked it backward, by first considering software
then hardware.
)

 

[PRNole]

Air holes my arse tom, dust can get into the vanes of a heat-sink and
block air flow, dust can get into the fins of a fan and cause it to stop
spinning, etc......

You claimed dust wasn't an issue, we've shown that it CAN be an issue,
as most of us have real experience with computers, unlike you.

His problem could still be heat related.

--
- Igitur qui desiderat pacem, praeparet bellum.
- Calling an illegal alien an "undocumented worker" is like calling a
  drug dealer an "unlicensed pharmacist"
(e-mail address removed) (remove 999 for proper email address)

Problem fixed!

Replaced the power supply with a higher rated one (new 400w in place
of original 250w) and the re-booting has not recurred.

Of course, I'm sure there's no surefire way to know if the re-booting
has actually stopped until the next re-boot occurs, and I may be in
some longer-than-usual-between-re-boot cycle due to some iatrogenic
cause, but I tried to force the re-boot and none has occurred. I
opened and closed over 25 Word documents at the same time I downloaded
a few files in the 450MB - 1GB range, had several applications running
at the same time, played a CD, etc., and still no re-boot. I left the
system running overnight and still no re-boot this morning.

Maybe it was the power supply...

Thanks to all for your help!

I now have another question but in a different thread, titled: "5 year-
old HP desktop RAM memory upgrade?"

..

 

[w_tom]

Of course, I'm sure there's no surefire way to know if the re-booting
has actually stopped until the next re-boot occurs, ...

Had you used the meter, then a power supply problem would have been
obvious. Trained techs use a meter to confirm a new supply will solve
a problem. You don't know if the reason for re-booting was eliminated
because you did not use a multimeter; did not see the problem before
fixing it. Was problem masked only because connectors were cleaned by
removing and replacing? Without numbers, nobody knows. Multimeter
was the surefire way to know.

Meanwhile a defective power supply can still boot and execute a
computer without restarting. Use a meter when computer puts the
supply under maximum load (less than 30 seconds of labor) to confirm
the new supply is sufficient and stable. Those numbers can detect a
defect before a supply causes strange restarts; before its warranty
expires.