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Could this be the battery? Appreciate any insights



 
 
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  #1  
Old October 18th 04, 03:08 AM
Hybyd2
external usenet poster
 
Posts: n/a
Default Could this be the battery? Appreciate any insights

This is a P3 733 MHz with an P34VX. The computer is on 24x7 - only the
monitor gets turned off when not in use, the disks are on and the system
does not go into standby or hibernate. One of the reason it's on 24x7 is
that if turned off, turning it on is a problem. And, when one succeeds in
turning it goes into the BIOS with the CPU speed set to Manual and a warning
that the CPU has been changed so its requesting the speed be set. I set it
at 733 and then all is well. Also, I've noticed the clock will need to be
reset once it goes into Windows as the time goes back to 1999 or some such
year. Could run for days / weeks until for whatever reason it gets turned
off. Because of the flaky behavior I've connected it to a UPS so your
normal brownout has no effect.

So what happens when it gets turned off? Typically, pressing the power
button has no response at all. It's totally dead. I then typically flip it
on it's side and open the case. There have been times when with the case
open pressing the power button has brought it back to life. It happened
again earlier this evening. With the computer open on it's side I actually
had to unplug it twice and replug it before it sprung to life. Some flaky
capacitor on the mother-board? Bad battery? If it's a bad battery,
wouldn't the only problem be that it wouldn't remember any bios settings?
Why would it refuse to start until I jumped through some still to be
determined mysterious set of steps.

Any insights into what the problem is would be greatly appreciated.

Thanks,

Henry


  #2  
Old October 18th 04, 03:35 AM
Michael W. Ryder
external usenet poster
 
Posts: n/a
Default

Hybyd2 wrote:
This is a P3 733 MHz with an P34VX. The computer is on 24x7 - only the
monitor gets turned off when not in use, the disks are on and the system
does not go into standby or hibernate. One of the reason it's on 24x7 is
that if turned off, turning it on is a problem. And, when one succeeds in
turning it goes into the BIOS with the CPU speed set to Manual and a warning
that the CPU has been changed so its requesting the speed be set. I set it
at 733 and then all is well. Also, I've noticed the clock will need to be
reset once it goes into Windows as the time goes back to 1999 or some such
year. Could run for days / weeks until for whatever reason it gets turned
off. Because of the flaky behavior I've connected it to a UPS so your
normal brownout has no effect.

So what happens when it gets turned off? Typically, pressing the power
button has no response at all. It's totally dead. I then typically flip it
on it's side and open the case. There have been times when with the case
open pressing the power button has brought it back to life. It happened
again earlier this evening. With the computer open on it's side I actually
had to unplug it twice and replug it before it sprung to life. Some flaky
capacitor on the mother-board? Bad battery? If it's a bad battery,
wouldn't the only problem be that it wouldn't remember any bios settings?
Why would it refuse to start until I jumped through some still to be
determined mysterious set of steps.

Any insights into what the problem is would be greatly appreciated.

Thanks,

Henry



Have you checked the power supply? I had similar problems getting a
computer to restart until I replaced the generic power supply with a PC
Power and Cooling one. No problems after that.
  #3  
Old October 18th 04, 03:54 AM
JAD
external usenet poster
 
Posts: n/a
Default

lol I have a PIII slot 1 850 in a P3V4x 'wacky' board, but a great
workhorse. same sort of situation except off on weekends. with a
windows9x Os i would occasionally get the cpu setup after a weird
shutdown (hangs etc) and the clock was always a little off. I think it
was a winbond thing. your problem seems to be cmos battery as the
problems seem to be chronic,every boot?

"Hybyd2" wrote in message
hlink.net...
This is a P3 733 MHz with an P34VX. The computer is on 24x7 - only

the
monitor gets turned off when not in use, the disks are on and the

system
does not go into standby or hibernate. One of the reason it's on

24x7 is
that if turned off, turning it on is a problem. And, when one

succeeds in
turning it goes into the BIOS with the CPU speed set to Manual and a

warning
that the CPU has been changed so its requesting the speed be set. I

set it
at 733 and then all is well. Also, I've noticed the clock will need

to be
reset once it goes into Windows as the time goes back to 1999 or

some such
year. Could run for days / weeks until for whatever reason it gets

turned
off. Because of the flaky behavior I've connected it to a UPS so

your
normal brownout has no effect.

So what happens when it gets turned off? Typically, pressing the

power
button has no response at all. It's totally dead. I then typically

flip it
on it's side and open the case. There have been times when with the

case
open pressing the power button has brought it back to life. It

happened
again earlier this evening. With the computer open on it's side I

actually
had to unplug it twice and replug it before it sprung to life. Some

flaky
capacitor on the mother-board? Bad battery? If it's a bad battery,
wouldn't the only problem be that it wouldn't remember any bios

settings?
Why would it refuse to start until I jumped through some still to be
determined mysterious set of steps.

Any insights into what the problem is would be greatly appreciated.

Thanks,

Henry




  #4  
Old October 18th 04, 05:24 AM
Matt
external usenet poster
 
Posts: n/a
Default

Hybyd2 wrote:

Any insights into what the problem is would be greatly appreciated.


A standard battery costs about $2.
  #5  
Old October 18th 04, 06:39 AM
David Maynard
external usenet poster
 
Posts: n/a
Default

Hybyd2 wrote:

This is a P3 733 MHz with an P34VX. The computer is on 24x7 - only the
monitor gets turned off when not in use, the disks are on and the system
does not go into standby or hibernate. One of the reason it's on 24x7 is
that if turned off, turning it on is a problem. And, when one succeeds in
turning it goes into the BIOS with the CPU speed set to Manual and a warning
that the CPU has been changed so its requesting the speed be set. I set it
at 733 and then all is well. Also, I've noticed the clock will need to be
reset once it goes into Windows as the time goes back to 1999 or some such
year. Could run for days / weeks until for whatever reason it gets turned
off. Because of the flaky behavior I've connected it to a UPS so your
normal brownout has no effect.

So what happens when it gets turned off? Typically, pressing the power
button has no response at all. It's totally dead. I then typically flip it
on it's side and open the case. There have been times when with the case
open pressing the power button has brought it back to life. It happened
again earlier this evening. With the computer open on it's side I actually
had to unplug it twice and replug it before it sprung to life. Some flaky
capacitor on the mother-board? Bad battery? If it's a bad battery,
wouldn't the only problem be that it wouldn't remember any bios settings?
Why would it refuse to start until I jumped through some still to be
determined mysterious set of steps.

Any insights into what the problem is would be greatly appreciated.

Thanks,

Henry



Dead CMOS battery. Replace it.

THEN see if there are 'other problems'.

  #6  
Old October 18th 04, 07:33 AM
Paul
external usenet poster
 
Posts: n/a
Default

In article k.net,
"Hybyd2" wrote:

This is a P3 733 MHz with an P34VX. The computer is on 24x7 - only the
monitor gets turned off when not in use, the disks are on and the system
does not go into standby or hibernate. One of the reason it's on 24x7 is
that if turned off, turning it on is a problem. And, when one succeeds in
turning it goes into the BIOS with the CPU speed set to Manual and a warning
that the CPU has been changed so its requesting the speed be set. I set it
at 733 and then all is well. Also, I've noticed the clock will need to be
reset once it goes into Windows as the time goes back to 1999 or some such
year. Could run for days / weeks until for whatever reason it gets turned
off. Because of the flaky behavior I've connected it to a UPS so your
normal brownout has no effect.

So what happens when it gets turned off? Typically, pressing the power
button has no response at all. It's totally dead. I then typically flip it
on it's side and open the case. There have been times when with the case
open pressing the power button has brought it back to life. It happened
again earlier this evening. With the computer open on it's side I actually
had to unplug it twice and replug it before it sprung to life. Some flaky
capacitor on the mother-board? Bad battery? If it's a bad battery,
wouldn't the only problem be that it wouldn't remember any bios settings?
Why would it refuse to start until I jumped through some still to be
determined mysterious set of steps.

Any insights into what the problem is would be greatly appreciated.

Thanks,

Henry


You could possible have one or two problems.

Try another power supply, as your current one could be having
a problem with +5VSB.

As for the time being off, have you ever cleared the CMOS on
this board, without switching off/disconnecting the PSU from
the wall ? Sometimes the ORing diode gets damaged, when the
CLRTC jumper shorts the +3V supply, and then, even if the
battery is good (reads about 3V), the clock could have trouble.
The ORing diode is a dual diode in a tiny three legged package
that looks like a transistor. Normally, this device is next
to the CMOS battery. One poster fixed his, by replacing the
three legged device, with a couple of 1N4148 type diodes. The
part typically has "K45" printed on it, in letters that can
only be read with a magnifying glass.

As far as diagnosing a bad dual diode, using a multimeter
to check the forward and reverse characteristics of the
dual diode would be one way to check it. Checking the battery
itself is pretty easy with a multimeter - it should read
3V when new, and the CMOS might become "forgetful" at around
2.4V (allowing 0.4V drop across the diode, and a minimum of
2.0V to run the Southbridge). The battery is only used, when
+5VSB is not available on the motherboard - the green
LED on an Asus motherboard is usually an indicator of the presence
of +5VSB, and when the green LED is lit, the CMOS clock and CMOS
RAM are running off +5VSB and no current flows out of the CMOS
battery.

The +5VSB is also part of the control circuit in the PSU. If
a power supply won't start when you press the power button, it
could be the +5VSB has "collapsed", and there is nothing to get
the rest of the PSU running. Another reason can be something
shorting to the bottom of the motherboard, such as an extra
standoff that doesn't line up with a plated (grounded) hole on
the motherboard. If a brass standoff touches a copper track on
the underside of the board, it can break just about anything it
touches.

HTH,
Paul
  #7  
Old October 18th 04, 12:21 PM
Dave Hines
external usenet poster
 
Posts: n/a
Default

Two problems:
Power Supply is marginal - replace it with a current generation PSU
(Antec NeoPower 480 or better $125 or PC Power & Cooling 400W + units)
Beware of PSU's that are cheap & under spec.
CMOS Battery is under voltage - that's why the date defaults back to 1999.

Hybyd2 wrote:
This is a P3 733 MHz with an P34VX. The computer is on 24x7 - only the
monitor gets turned off when not in use, the disks are on and the system
does not go into standby or hibernate. One of the reason it's on 24x7 is
that if turned off, turning it on is a problem. And, when one succeeds in
turning it goes into the BIOS with the CPU speed set to Manual and a warning
that the CPU has been changed so its requesting the speed be set. I set it
at 733 and then all is well. Also, I've noticed the clock will need to be
reset once it goes into Windows as the time goes back to 1999 or some such
year. Could run for days / weeks until for whatever reason it gets turned
off. Because of the flaky behavior I've connected it to a UPS so your
normal brownout has no effect.

So what happens when it gets turned off? Typically, pressing the power
button has no response at all. It's totally dead. I then typically flip it
on it's side and open the case. There have been times when with the case
open pressing the power button has brought it back to life. It happened
again earlier this evening. With the computer open on it's side I actually
had to unplug it twice and replug it before it sprung to life. Some flaky
capacitor on the mother-board? Bad battery? If it's a bad battery,
wouldn't the only problem be that it wouldn't remember any bios settings?
Why would it refuse to start until I jumped through some still to be
determined mysterious set of steps.

Any insights into what the problem is would be greatly appreciated.

Thanks,

Henry


  #8  
Old October 18th 04, 01:49 PM
Hybyd2
external usenet poster
 
Posts: n/a
Default

I appreciate all the responses from folks who took the time to do so. I do
realize based on this and other responses that the battery by itself would
not cause the startup problems. That there could be problems with the PSU.
Some basic followup questions (I'm a newbie):

1) About checking the battery: if a multi-meter reads 3.0V is this a
definitive sign that the battery is good? Or, can it read 3V when the
battery is out of the board and still not perform under load? Since the
system is running at this point and acts as my web-server, I'm reluctant to
experiment with it until I have a good plan of action. But I do have a
spare battery which registers 3.1 using a multi-meter.
2) Paul, in response to your question below about clearing the CMOS. If
that involves manipulating jumpers on the board, no I've never done this in
the year and a half that I've owned the computer (I bought it used).
3) If the battery is dead and the system unplugged from the wall power
socket is it a given that this (P34VX) system will lose it's clock setting?
I do realize based on what Paul's said before that there are other ways for
the clock to lose it's setting but I'm curious if the answer to the question
in the previous sentence is guaranteed to be yes.
4) If the battery is dead and the system unplugged from the wall power
socket is it a given that this (P34VX) system will lose it's knowledge of
what CPU is plugged in - as I mentioned when it does startup it goes into
the Advanced bios setup screen with the CPU speed at Manual and in the right
column saying that I've changed the CPU and so should adjust the speed.
5) If the +5VSB has collapsed is there a way to jump start the PSU / board?
6) What's really puzzling (to me) is that there is some weird sequence which
causes it to start. ???

Thanks,

Henry



"Paul" wrote in message
...
In article k.net,
"Hybyd2" wrote:

This is a P3 733 MHz with an P34VX. The computer is on 24x7 - only the
monitor gets turned off when not in use, the disks are on and the system
does not go into standby or hibernate. One of the reason it's on 24x7 is
that if turned off, turning it on is a problem. And, when one succeeds
in
turning it goes into the BIOS with the CPU speed set to Manual and a
warning
that the CPU has been changed so its requesting the speed be set. I set
it
at 733 and then all is well. Also, I've noticed the clock will need to
be
reset once it goes into Windows as the time goes back to 1999 or some
such
year. Could run for days / weeks until for whatever reason it gets
turned
off. Because of the flaky behavior I've connected it to a UPS so your
normal brownout has no effect.

So what happens when it gets turned off? Typically, pressing the power
button has no response at all. It's totally dead. I then typically flip
it
on it's side and open the case. There have been times when with the case
open pressing the power button has brought it back to life. It happened
again earlier this evening. With the computer open on it's side I
actually
had to unplug it twice and replug it before it sprung to life. Some
flaky
capacitor on the mother-board? Bad battery? If it's a bad battery,
wouldn't the only problem be that it wouldn't remember any bios settings?
Why would it refuse to start until I jumped through some still to be
determined mysterious set of steps.

Any insights into what the problem is would be greatly appreciated.

Thanks,

Henry


You could possible have one or two problems.

Try another power supply, as your current one could be having
a problem with +5VSB.

As for the time being off, have you ever cleared the CMOS on
this board, without switching off/disconnecting the PSU from
the wall ? Sometimes the ORing diode gets damaged, when the
CLRTC jumper shorts the +3V supply, and then, even if the
battery is good (reads about 3V), the clock could have trouble.
The ORing diode is a dual diode in a tiny three legged package
that looks like a transistor. Normally, this device is next
to the CMOS battery. One poster fixed his, by replacing the
three legged device, with a couple of 1N4148 type diodes. The
part typically has "K45" printed on it, in letters that can
only be read with a magnifying glass.

As far as diagnosing a bad dual diode, using a multimeter
to check the forward and reverse characteristics of the
dual diode would be one way to check it. Checking the battery
itself is pretty easy with a multimeter - it should read
3V when new, and the CMOS might become "forgetful" at around
2.4V (allowing 0.4V drop across the diode, and a minimum of
2.0V to run the Southbridge). The battery is only used, when
+5VSB is not available on the motherboard - the green
LED on an Asus motherboard is usually an indicator of the presence
of +5VSB, and when the green LED is lit, the CMOS clock and CMOS
RAM are running off +5VSB and no current flows out of the CMOS
battery.

The +5VSB is also part of the control circuit in the PSU. If
a power supply won't start when you press the power button, it
could be the +5VSB has "collapsed", and there is nothing to get
the rest of the PSU running. Another reason can be something
shorting to the bottom of the motherboard, such as an extra
standoff that doesn't line up with a plated (grounded) hole on
the motherboard. If a brass standoff touches a copper track on
the underside of the board, it can break just about anything it
touches.

HTH,
Paul



  #9  
Old October 18th 04, 06:19 PM
Al Smith
external usenet poster
 
Posts: n/a
Default

This is a P3 733 MHz with an P34VX. The computer is on 24x7 - only the
monitor gets turned off when not in use, the disks are on and the system
does not go into standby or hibernate. One of the reason it's on 24x7 is
that if turned off, turning it on is a problem. And, when one succeeds in
turning it goes into the BIOS with the CPU speed set to Manual and a warning
that the CPU has been changed so its requesting the speed be set. I set it
at 733 and then all is well. Also, I've noticed the clock will need to be
reset once it goes into Windows as the time goes back to 1999 or some such
year. Could run for days / weeks until for whatever reason it gets turned
off. Because of the flaky behavior I've connected it to a UPS so your
normal brownout has no effect.

So what happens when it gets turned off? Typically, pressing the power
button has no response at all. It's totally dead. I then typically flip it
on it's side and open the case. There have been times when with the case
open pressing the power button has brought it back to life. It happened
again earlier this evening. With the computer open on it's side I actually
had to unplug it twice and replug it before it sprung to life. Some flaky
capacitor on the mother-board? Bad battery? If it's a bad battery,
wouldn't the only problem be that it wouldn't remember any bios settings?
Why would it refuse to start until I jumped through some still to be
determined mysterious set of steps.

Any insights into what the problem is would be greatly appreciated.

Thanks,


The only insight I have is that it's time to upgrade. Why are you
hanging onto a P3 that won't boot, when for around $100 you could
buy a P3 that *will* boot? Or better still, spend $500 and get a
more modern computer with some power.
  #10  
Old October 18th 04, 06:53 PM
Zotin Khuma
external usenet poster
 
Posts: n/a
Default

David Maynard wrote in message ...
Hybyd2 wrote:

This is a P3 733 MHz with an P34VX. The computer is on 24x7 - only the
monitor gets turned off when not in use, the disks are on and the system
does not go into standby or hibernate. One of the reason it's on 24x7 is
that if turned off, turning it on is a problem. And, when one succeeds in
turning it goes into the BIOS with the CPU speed set to Manual and a warning
that the CPU has been changed so its requesting the speed be set. I set it
at 733 and then all is well. Also, I've noticed the clock will need to be
reset once it goes into Windows as the time goes back to 1999 or some such
year. Could run for days / weeks until for whatever reason it gets turned
off. Because of the flaky behavior I've connected it to a UPS so your
normal brownout has no effect.

So what happens when it gets turned off? Typically, pressing the power
button has no response at all. It's totally dead. I then typically flip it
on it's side and open the case. There have been times when with the case
open pressing the power button has brought it back to life. It happened
again earlier this evening. With the computer open on it's side I actually
had to unplug it twice and replug it before it sprung to life. Some flaky
capacitor on the mother-board? Bad battery? If it's a bad battery,
wouldn't the only problem be that it wouldn't remember any bios settings?
Why would it refuse to start until I jumped through some still to be
determined mysterious set of steps.

Any insights into what the problem is would be greatly appreciated.

Thanks,

Henry



Dead CMOS battery. Replace it.

THEN see if there are 'other problems'.


I've seen a few motherboards that run fine with a good CMOS battery or
with none, but have great difficulty starting with a weak one. The
difference between a good battery and none is it won't retain settings
with none after a power-down.
 




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