Lm_sensors making little sense...

[r***@webworxshop.com]

Hi All,

I'm setting up Lm_sensors on my new Arch Linux system. Everything
appears to be working, however I'm getting out values that bear no
relation to those reported by the BIOS. The output of the sensors
command is:

k10temp-pci-00c3
Adapter: PCI adapter
temp1: +17.6°C (high = +70.0°C)
(crit = +70.0°C, hyst = +69.0°C)

it8720-isa-0228
Adapter: ISA adapter
in0: +1.02 V (min = +0.00 V, max = +4.08 V)
in1: +1.50 V (min = +0.00 V, max = +4.08 V)
in2: +3.36 V (min = +0.00 V, max = +4.08 V)
+5V: +3.07 V (min = +0.00 V, max = +4.08 V)
in4: +3.06 V (min = +0.00 V, max = +4.08 V)
in5: +2.16 V (min = +0.00 V, max = +4.08 V)
in6: +2.16 V (min = +0.00 V, max = +4.08 V)
5VSB: +3.02 V (min = +0.00 V, max = +4.08 V)
Vbat: +3.15 V
fan1: 949 RPM (min = 10 RPM)
fan2: 1541 RPM (min = 10 RPM)
fan3: 0 RPM (min = 0 RPM)
temp1: +41.0°C (low = +127.0°C, high = +127.0°C) sensor =
thermistor
temp2: +79.0°C (low = +127.0°C, high = +127.0°C) sensor =
thermistor
temp3: +17.0°C (low = +127.0°C, high = +70.0°C) sensor =
thermistor

This is with all three cores on my CPU idling (<2% usage) and the
frequency being automatically scaled back to 800MHz. A quick reboot to
the BIOS reveals the real values to be:

System temperature: 40°C
CPU Temperature: 28°C
CPU Fan: ~1566RPM
System Fan: ~1548RPM

It looks like one of the fan readings is pretty much correct and
perhaps temp1 relates to the system temp. Nothing else makes much sense
though and temp2 is very weird. According to <insert search engine here>
lm_sensors can be configured to convert the raw values differently with
expression lines in it's configuration file. However, the only part
which seems to relate to my detected hardware is:

chip "it87-*" "it8712-*" "it8716-*" "it8718-*" "it8720-*"

label in8 "Vbat"

...and even if I found the correct part I would have no idea what the
correct conversion expressions would be.

Does anyone have any tips for configuring this for a specific
motherboard? The motherboard in question is a Gigabyte A75M-D2H.

Thanks in advance,

Rob Connolly



_______________________________________________
NZLUG mailing list ***@linux.net.nz
http://www.linux.net.nz/cgi-bin/mailman/listinfo/nzlug

[Volker Kuhlmann]

Post by r***@webworxshop.com
Does anyone have any tips for configuring this for a specific
motherboard? The motherboard in question is a Gigabyte A75M-D2H.

1) Dig deep into the lm-sensors documentation.

2) Remove everything from config file that does not belong to your mobo
chip (according to docs that shouldn't be necessary, but I've had bad
screwups with the config file parsing).

3) Take wild guesses at dividers, scalers and offsets for each value in
the config file.

4) Compare with BIOS displayed values at low/med/high temperature and
fan speed for each value.

5) Repeat from 3) until blue in face.

Obviously google for any config file for that mobo.
You could also ask on the mailing list for tips, but take anything you
get as a bonus. It's not that they don't want to help, but they can't.

The problem is that as long as mobo manufacturers treat this as a "who
cares, our mickeysoft driver displays it fine" you're stuffed.

Volker