* Re: [lm-sensors] small changes in configuration file for MSI
2010-08-28 23:16 [lm-sensors] small changes in configuration file for MSI IM-945GSE-A Leo Krüger
@ 2010-08-30 8:23 ` Jean Delvare
2010-08-30 8:50 ` Leo Krüger
2010-08-30 9:34 ` Jean Delvare
2 siblings, 0 replies; 4+ messages in thread
From: Jean Delvare @ 2010-08-30 8:23 UTC (permalink / raw)
To: lm-sensors
Hi Leo,
On Sun, 29 Aug 2010 01:16:17 +0200, Leo Krüger wrote:
> I own a MSI IM-945GSE-A motherboard and used the sample configuration file
> from http://lm-sensors.org/wiki/Configurations/MSI/IM-945GSE-A,
> which showed me around 14V for the 12V output.
I'm adding the original author of the configuration file to Cc.
> Since this would be far above specification limits, I measured the actual
> values at the ATX power connector. In addition to the 12V output, the 5V
> and the 5Vsb line differed a little.
I am a little curious about your experimental setup. How do you get
access to the ATX power connector while the system is running?
I usually measure +5V and +12V from molex connectors, it's easy. But
5VSB, I wouldn't know how to measure it.
> Below is my updated configuration file. Note that I just changed 3 lines,
> the compute lines for in4, in5 and in6.
> It would be nice if you could update the sample file in your wiki.
> Let me know if any additional steps are necessary.
It is expected that measuring the values with a multimeter will lead to
slightly different results for voltages which need scaling. Scaling is
achieved using two resistors, the value of which is typically
guaranteed to 1%. Therefore, there can be up to 2% of error introduced
by the resistors themselves. By calibrating your configuration file
based on actual measurement, you correct this error for your specific
motherboard, but the same correction doesn't apply to other instances
of this motherboard model.
So your proposed changes may be perfect for your board, but aren't
suitable for the default configuration file for this board.
A better way to figure out which scaling factors are intended by the
board manufacturer, is to compare with what the BIOS is printing. First
write down all values reported by the BIOS, and also note your
voltmeter measurement. Then do the same again with lm-sensors's
unscaled voltage values. If the voltmeter values didn't change, then
lm-sensors should report the same as the BIOS after scaling. If the
voltmeter values changed (which can happen as the system load is
slightly different) then you have to take it into account in your
computations.
The 5.25 scaling factor comes straight from the datasheet (suggested
resistors of 200k and 47k), and your own measurement for +5V leads to
almost exactly this, so I wouldn't change it. It is also quite unlikely
that the vendor would use different resistor values for +5V and 5VSB,
which makes me reluctant to change 5VSB either, although your proposal
is quite different there.
For +12V, the 12.83 scaling factor was apparently copied from our old
default configuration file, which for this chip was written for an
Epox board. The datasheet instead suggests to use resistors of 200k and
20k, leading to a scaling factor of 11. Note that the difference
between this 11 and your 10.86 is less than 2%, so it is likely that
MSI followed to the datasheet. So I would go with 11.
--
Jean Delvare
http://khali.linux-fr.org/wishlist.html
_______________________________________________
lm-sensors mailing list
lm-sensors@lm-sensors.org
http://lists.lm-sensors.org/mailman/listinfo/lm-sensors
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [lm-sensors] small changes in configuration file for MSI
2010-08-28 23:16 [lm-sensors] small changes in configuration file for MSI IM-945GSE-A Leo Krüger
2010-08-30 8:23 ` [lm-sensors] small changes in configuration file for MSI Jean Delvare
@ 2010-08-30 8:50 ` Leo Krüger
2010-08-30 9:34 ` Jean Delvare
2 siblings, 0 replies; 4+ messages in thread
From: Leo Krüger @ 2010-08-30 8:50 UTC (permalink / raw)
To: lm-sensors
Hi Jean,
> -----Ursprüngliche Nachricht-----
> Von: Jean Delvare [mailto:khali@linux-fr.org]
> Gesendet: Montag, 30. August 2010 10:24
> An: Leo Krüger
> Cc: lm-sensors@lm-sensors.org; Thomas Ettwein
> Betreff: Re: [lm-sensors] small changes in configuration file for MSI
> IM-945GSE-A
>
> Hi Leo,
>
> On Sun, 29 Aug 2010 01:16:17 +0200, Leo Krüger wrote:
> > I own a MSI IM-945GSE-A motherboard and used the sample configuration
> file
> > from http://lm-sensors.org/wiki/Configurations/MSI/IM-945GSE-A,
> > which showed me around 14V for the 12V output.
>
> I'm adding the original author of the configuration file to Cc.
>
> > Since this would be far above specification limits, I measured the
> actual
> > values at the ATX power connector. In addition to the 12V output, the
> 5V
> > and the 5Vsb line differed a little.
>
> I am a little curious about your experimental setup. How do you get
> access to the ATX power connector while the system is running?
For my atx power connector it was possible to get to conducting parts with a
small test prod.
>
> I usually measure +5V and +12V from molex connectors, it's easy. But
> 5VSB, I wouldn't know how to measure it.
>
http://en.wikipedia.org/wiki/ATX#Power_supply
the purple wire is 5vsb
> > Below is my updated configuration file. Note that I just changed 3
> lines,
> > the compute lines for in4, in5 and in6.
> > It would be nice if you could update the sample file in your wiki.
> > Let me know if any additional steps are necessary.
>
> It is expected that measuring the values with a multimeter will lead to
> slightly different results for voltages which need scaling. Scaling is
> achieved using two resistors, the value of which is typically
> guaranteed to 1%. Therefore, there can be up to 2% of error introduced
> by the resistors themselves. By calibrating your configuration file
> based on actual measurement, you correct this error for your specific
> motherboard, but the same correction doesn't apply to other instances
> of this motherboard model.
>
> So your proposed changes may be perfect for your board, but aren't
> suitable for the default configuration file for this board.
>
> A better way to figure out which scaling factors are intended by the
> board manufacturer, is to compare with what the BIOS is printing. First
> write down all values reported by the BIOS, and also note your
> voltmeter measurement. Then do the same again with lm-sensors's
> unscaled voltage values. If the voltmeter values didn't change, then
> lm-sensors should report the same as the BIOS after scaling. If the
> voltmeter values changed (which can happen as the system load is
> slightly different) then you have to take it into account in your
> computations.
I've to admit that this sounds much more reliable than my simple
measurements.
To check your proposed factors I'm going to do it the way you suggested.
Afterwards I will give you an acknowledgement.
I've access to two of these motherboards, so I will check if the results
differ.
>
> The 5.25 scaling factor comes straight from the datasheet (suggested
> resistors of 200k and 47k), and your own measurement for +5V leads to
> almost exactly this, so I wouldn't change it. It is also quite unlikely
> that the vendor would use different resistor values for +5V and 5VSB,
> which makes me reluctant to change 5VSB either, although your proposal
> is quite different there.
Ok. I think you're right. The difference is quite marginal.
>
> For +12V, the 12.83 scaling factor was apparently copied from our old
> default configuration file, which for this chip was written for an
> Epox board. The datasheet instead suggests to use resistors of 200k and
> 20k, leading to a scaling factor of 11. Note that the difference
> between this 11 and your 10.86 is less than 2%, so it is likely that
> MSI followed to the datasheet. So I would go with 11.
>
I just found the datasheet
http://www.fintek.com.tw/files/productfiles/F71882_ab.pdf
To which one do you refer?
Please let me know if I can do anything else.
Especially if there is anything I can do to provide you with hardware
specific data
to support development of lm-sensors (I actually don't know if there is
support missing for any of the hardware parts)
Regards,
Leo
> --
> Jean Delvare
> http://khali.linux-fr.org/wishlist.html
_______________________________________________
lm-sensors mailing list
lm-sensors@lm-sensors.org
http://lists.lm-sensors.org/mailman/listinfo/lm-sensors
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [lm-sensors] small changes in configuration file for MSI
2010-08-28 23:16 [lm-sensors] small changes in configuration file for MSI IM-945GSE-A Leo Krüger
2010-08-30 8:23 ` [lm-sensors] small changes in configuration file for MSI Jean Delvare
2010-08-30 8:50 ` Leo Krüger
@ 2010-08-30 9:34 ` Jean Delvare
2 siblings, 0 replies; 4+ messages in thread
From: Jean Delvare @ 2010-08-30 9:34 UTC (permalink / raw)
To: lm-sensors
On Mon, 30 Aug 2010 10:50:57 +0200, Leo Krüger wrote:
> Hi Jean,
> > I am a little curious about your experimental setup. How do you get
> > access to the ATX power connector while the system is running?
>
> For my atx power connector it was possible to get to conducting parts with a
> small test prod.
>
> >
> > I usually measure +5V and +12V from molex connectors, it's easy. But
> > 5VSB, I wouldn't know how to measure it.
> >
>
> http://en.wikipedia.org/wiki/ATX#Power_supply
> the purple wire is 5vsb
I know that, but I have no easy access to it when the system is up and
running, contrary to +5V.
> > (...)
> > A better way to figure out which scaling factors are intended by the
> > board manufacturer, is to compare with what the BIOS is printing. First
> > write down all values reported by the BIOS, and also note your
> > voltmeter measurement. Then do the same again with lm-sensors's
> > unscaled voltage values. If the voltmeter values didn't change, then
> > lm-sensors should report the same as the BIOS after scaling. If the
> > voltmeter values changed (which can happen as the system load is
> > slightly different) then you have to take it into account in your
> > computations.
>
> I've to admit that this sounds much more reliable than my simple
> measurements.
> To check your proposed factors I'm going to do it the way you suggested.
> Afterwards I will give you an acknowledgement.
> I've access to two of these motherboards, so I will check if the results
> differ.
OK, great.
> (...)
> I just found the datasheet
> http://www.fintek.com.tw/files/productfiles/F71882_ab.pdf
> To which one do you refer?
This is only a product brief, I was referring to the complete datasheet
for the device. Not sure if it can be downloaded publicly, I think I
got that one from our technical contacts at Fintek.
> Please let me know if I can do anything else.
> Especially if there is anything I can do to provide you with hardware
> specific data
> to support development of lm-sensors (I actually don't know if there is
> support missing for any of the hardware parts)
There is definitely support missing for many parts, but the hard part
is to get the datasheets and then write and review the driver code.
For board configurations, you can definitely help. If you can
contribute configuration files for all boards you have, this would be
welcome.
--
Jean Delvare
http://khali.linux-fr.org/wishlist.html
_______________________________________________
lm-sensors mailing list
lm-sensors@lm-sensors.org
http://lists.lm-sensors.org/mailman/listinfo/lm-sensors
^ permalink raw reply [flat|nested] 4+ messages in thread