CMOS checksum fails

On Mon, 04 May 2015 12:10:09 -0400, Skybuck Flying
wrote:

It's my Dream PC from 2006, repaired and down graded throughout the
years (until 2015 soon I may build a new computer since 2016 is coming
and I promised myself a new computer for 2016 )

It's on basically every day for 10 hours or so at least.

I put the computer into sleep mode.

Perhaps sleep mode keeps the CMOS settings alive ?


So, with 14 hours of off-time per day and 24,000 hours of CMOS power
according
to Paul, your battery should've failed 4.7 years after 2006, i.e., mid
2010,
instead of 9 years later in early 2015, if it wasn't being recharged ...
I also
have a computer which operated for about a decade with many more hours of
off-time.
The CR2032 never failed. Even if we reduce the CMOS amp draw by half, you
can
easily compute that the battery should've failed at about 7.5 years. I
also know
first hand that the technique I mentioned earlier on recharging the CMOS
battery
works. Of course, it used a battery much larger in diameter than the
CR2032.
Given that the CR2032s are apparently not dying as fast as they should for
a
supposedly non-rechargeable battery, I think it's valid to conclude
something
else is going on with Li-ion CR2032s : 1) battery draw is much, much lower
than
expected for CMOS, or 2) the Li-ion CR2032's are actually being recharged
from
the motherboard. Wikipedia says ATX motherboards continue to power CMOS
as long
as the machine is plugged in. So, it wouldn't be hours of off-time where
CMOS
consumes power, but hours of unplugged-time for ATX machines where CMOS
consumes
power. That could extend the battery life to many decades. Of course,
your
motherboard might use something other than CR2032, most of which are
actually
rechargeable but recquire desoldering.


Rod Pemberton

--
Cars kill more people than guns in the U.S.
Yet, no one is trying to take away your car.

On Tue, 05 May 2015 09:17:12 +1000, David Eather wrote:

On Mon, 04 May 2015 21:45:43 +1000, Pimpom
wrote:


"Rod Pemberton" wrote in message
newsp.xx3xr8t5wa0t4m@localhost...
On Sun, 03 May 2015 21:26:48 -0400, Skybuck Flying
wrote:

I guess it's battery:

[link]

Kinda weird... it seems to keep some settings but maybe that's
not true.

Those are probably default BIOS settings.

The clock/date is reset to 2005 causing weird problems in
windows
and apps which is easily solved.

So I guess that's a clear symptom that battery might be dead.

I ll try replacing it sometime in future perhaps and see if
that
solves it.

The battery might not need replacing. If the motherboard
hasn't been
used in a long time, the battery may simply need recharging.
You can
do this by powering the board for a few hours, and then using
it daily
for a week or so. Then, don't use the motherboard for a month
or so.
If the settings are lost after a month without use, replace the
battery.

I'm afraid I have to disagree. Motherboards use primary
(non-rechargeable) CR2032 batteries. As with most primary
batteries, they may partially recover when they are left
unloaded. This is what happens when the computer is turned on and
the power supply takes over the job of supplying the tiny amount
of power needed to retain the BIOS settings. This is why a CMOS
battery actually lasts longer if the computer is in regular use.

That said, it is often possible to rejuvenate a primary cell to
some extent by charging it, but it's not as good as recharging a
secondary cell And the practice is often discouraged because it
can produce undesireable consequences, even to the extent of
exploding.



I have seen both used on motherboards. But the rechargeable is normally
a small stack of 3 x 1.2v NiCd. After a few years they tend to leak and
ruin the main board shortly after that.

Just thinking it's been many years since Ive seen one - it was a 386 or
maybe 486

My DreamPC died a couple of times.

Last time it died and was repaired was 30 november 2012.

I fried the motherboard by misplacing a usb connector on a usb header.

The fried motherboard was replaced with a "second hand" motherboard from a
special dealer who trades in used electronics.

So this motherboard has had power for 3 years almost non-stop, that's why I
am a little bit surprised that the battery might be dead.

When I think about this possibility it seems unlikely to me, hence my
surprise.

Perhaps there is something else causing the checksum error.

For now I will assume the battery is the problem.

But I wouldn't be surprised if it's some strange electrical or magnetic
interference problem.

For now it's not a problem to leave the "dead" battery in.

I rather leave it in then risking any further damage to my computer.

Maybe when I buy a new computer, I might replace the battery of the old
one... just to see if this was indeed the problem

Bye,
Skybuck.

Let's suppose for a moment that the battery should not have failed and it's
indeed "dead"/out of power.

Perhaps there is a short circuit on the motherboard being caused by dusts,
hairs or other small little elements...

Perhaps small little metal atoms blown in.

Perhaps this dust could lead to a very small short circuit... drawing away
power from the battery.

Just a little theorie/hypothesis to explain the short life of the battery.

Bye,
Skybuck.

On Tue, 5 May 2015 11:55:03 +0200, "Skybuck Flying"
Gave us:

So this motherboard has had power for 3 years almost non-stop, that's why I
am a little bit surprised that the battery might be dead.


You are a true idiot. Go **** and moan in a children's group.

On Tue, 5 May 2015 11:58:17 +0200, "Skybuck Flying"
Gave us:

Let's suppose for a moment that the battery should not have failed and it's
indeed "dead"/out of power.

Perhaps there is a short circuit on the motherboard being caused by dusts,
hairs or other small little elements...

Perhaps small little metal atoms blown in.

Perhaps this dust could lead to a very small short circuit... drawing away
power from the battery.

Just a little theorie/hypothesis to explain the short life of the battery.

Bye,
Skybuck.


I would suggest taking an electronics course, but that too is miles
above your brain grade.

"David Eather" wrote in message
news
On Tue, 05 May 2015 09:17:12 +1000, David Eather
wrote:

On Mon, 04 May 2015 21:45:43 +1000, Pimpom
wrote:


"Rod Pemberton" wrote in message
newsp.xx3xr8t5wa0t4m@localhost...
On Sun, 03 May 2015 21:26:48 -0400, Skybuck Flying
wrote:

I guess it's battery:

[link]

Kinda weird... it seems to keep some settings but maybe
that's
not true.

Those are probably default BIOS settings.

The clock/date is reset to 2005 causing weird problems in
windows
and apps which is easily solved.

So I guess that's a clear symptom that battery might be
dead.

I ll try replacing it sometime in future perhaps and see if
that
solves it.

The battery might not need replacing. If the motherboard
hasn't been
used in a long time, the battery may simply need recharging.
You can
do this by powering the board for a few hours, and then
using
it daily
for a week or so. Then, don't use the motherboard for a
month
or so.
If the settings are lost after a month without use, replace
the
battery.

I'm afraid I have to disagree. Motherboards use primary
(non-rechargeable) CR2032 batteries. As with most primary
batteries, they may partially recover when they are left
unloaded. This is what happens when the computer is turned on
and
the power supply takes over the job of supplying the tiny
amount
of power needed to retain the BIOS settings. This is why a
CMOS
battery actually lasts longer if the computer is in regular
use.

That said, it is often possible to rejuvenate a primary cell
to
some extent by charging it, but it's not as good as
recharging a
secondary cell And the practice is often discouraged because
it
can produce undesireable consequences, even to the extent of
exploding.



I have seen both used on motherboards. But the rechargeable is
normally a small stack of 3 x 1.2v NiCd. After a few years
they tend to leak and ruin the main board shortly after that.

Just thinking it's been many years since Ive seen one - it was
a 386 or maybe 486

I saw some of those in the Pentium era too but they were in the
minority even then. I didn't mention them earlier to avoid
clutter. I also came across some mobos that had no battery
visible anywhere. They kept time and retained BIOS settings, so
the battery was no doubt inside the boxy RTC module.

On Tue, 05 May 2015 10:48:36 +1000 "David Eather"
wrote in Message id: :

On Tue, 05 May 2015 09:17:12 +1000, David Eather wrote:

On Mon, 04 May 2015 21:45:43 +1000, Pimpom
wrote:


"Rod Pemberton" wrote in message
newsp.xx3xr8t5wa0t4m@localhost...
On Sun, 03 May 2015 21:26:48 -0400, Skybuck Flying
wrote:

I guess it's battery:

[link]

Kinda weird... it seems to keep some settings but maybe that's
not true.

Those are probably default BIOS settings.

The clock/date is reset to 2005 causing weird problems in
windows
and apps which is easily solved.

So I guess that's a clear symptom that battery might be dead.

I ll try replacing it sometime in future perhaps and see if
that
solves it.

The battery might not need replacing. If the motherboard
hasn't been
used in a long time, the battery may simply need recharging.
You can
do this by powering the board for a few hours, and then using
it daily
for a week or so. Then, don't use the motherboard for a month
or so.
If the settings are lost after a month without use, replace the
battery.

I'm afraid I have to disagree. Motherboards use primary
(non-rechargeable) CR2032 batteries. As with most primary
batteries, they may partially recover when they are left
unloaded. This is what happens when the computer is turned on and
the power supply takes over the job of supplying the tiny amount
of power needed to retain the BIOS settings. This is why a CMOS
battery actually lasts longer if the computer is in regular use.

That said, it is often possible to rejuvenate a primary cell to
some extent by charging it, but it's not as good as recharging a
secondary cell And the practice is often discouraged because it
can produce undesireable consequences, even to the extent of
exploding.



I have seen both used on motherboards. But the rechargeable is normally
a small stack of 3 x 1.2v NiCd. After a few years they tend to leak and
ruin the main board shortly after that.

Just thinking it's been many years since Ive seen one - it was a 386 or
maybe 486

That is true. Around the era of the first socket 5 and socket 7 Pentiums,
many motherboards went to encapsulated NVRAM devices with a built in
clocks from the likes of Dallas/Maxim. In the Pentium 2 and Pentium 3 era
most went to CR2032 coin cells.

On Tue, 5 May 2015 20:31:48 +0530, "Pimpom"
wrote:


"David Eather" wrote in message
news
On Tue, 05 May 2015 09:17:12 +1000, David Eather
wrote:

On Mon, 04 May 2015 21:45:43 +1000, Pimpom
wrote:


"Rod Pemberton" wrote in message
newsp.xx3xr8t5wa0t4m@localhost...
On Sun, 03 May 2015 21:26:48 -0400, Skybuck Flying
wrote:

I guess it's battery:

[link]

Kinda weird... it seems to keep some settings but maybe
that's
not true.

Those are probably default BIOS settings.

The clock/date is reset to 2005 causing weird problems in
windows
and apps which is easily solved.

So I guess that's a clear symptom that battery might be
dead.

I ll try replacing it sometime in future perhaps and see if
that
solves it.

The battery might not need replacing. If the motherboard
hasn't been
used in a long time, the battery may simply need recharging.
You can
do this by powering the board for a few hours, and then
using
it daily
for a week or so. Then, don't use the motherboard for a
month
or so.
If the settings are lost after a month without use, replace
the
battery.

I'm afraid I have to disagree. Motherboards use primary
(non-rechargeable) CR2032 batteries. As with most primary
batteries, they may partially recover when they are left
unloaded. This is what happens when the computer is turned on
and
the power supply takes over the job of supplying the tiny
amount
of power needed to retain the BIOS settings. This is why a
CMOS
battery actually lasts longer if the computer is in regular
use.

That said, it is often possible to rejuvenate a primary cell
to
some extent by charging it, but it's not as good as
recharging a
secondary cell And the practice is often discouraged because
it
can produce undesireable consequences, even to the extent of
exploding.



I have seen both used on motherboards. But the rechargeable is
normally a small stack of 3 x 1.2v NiCd. After a few years
they tend to leak and ruin the main board shortly after that.

Just thinking it's been many years since Ive seen one - it was
a 386 or maybe 486

I saw some of those in the Pentium era too but they were in the
minority even then. I didn't mention them earlier to avoid
clutter. I also came across some mobos that had no battery
visible anywhere. They kept time and retained BIOS settings, so
the battery was no doubt inside the boxy RTC module.

Yeah, Dallas Semiconductor had a bunch of RTCs with the battery built
in. Dallas had some nice stuff but was eaten by Maxim.

DecadentLinuxUserNumeroUno wrote:
I would suggest taking an electronics course, but that too is miles
above your brain grade.

Fact: The vast majority of college students have no idea how a
flashlight works. The concept of "circuit" is not familiar to them.