Question about it87 on an ECS K7S5A

John Gruenenfelder johng at
Tue Nov 19 03:51:18 CET 2002

Hello.  I have an ECS K7S5A v3.0 motherboard.  Using the information in the
K7S5A-HOWTO, I have the sensors mostly set up correctly.  This board uses an
it87 chip (loaded as 'modprobe it87 temp_type=0x31').

Anyway, I have the fan and temperature settings just fine, but am still having
trouble with the voltage settings.

The HOWTO suggests:

label in0 "VCore"
label in1 "Vcc2.5v"
label in2 "Vcc5v"
label in3 "+5V"
label in4 "+12V"
label in5 "-12V"
label in6 "-5V"
label in7 "SB 5V"
label in8 "V battery"

The mobo BIOS, however, lists the voltages as (I assume in the same order):


The odd this about this arrangement is that there is only one negative
voltage.  There is no -5V sensor.  Considering that one must be wrong in some
way, I have settled on the follow list:

    label in0 "VCore 1"
    label in1 "Vcc2.5V"
    label in2 "Vcc3.3V"
    label in3 "+5V"
    label in4 "+12V"
    label in5 "-12V"
    label in6 "-5V"
    label in7 "5V SB"
    label in8 "VBat"

The lm_sensors supplied sensors.conf has a section:

# this much simpler version is reported to work for a
# Eltite Group K7S5A board
   compute in5 -(36/10)*@, -@/(36/10)
   compute in6 -(56/10)*@, -@/(56/10)

This works well to give me a -12V reading, but for the -5V reading (in6) my
value is always around -5.60V.  Since I can't check this in the BIOS, I don't
really know what the problem is.  Maybe it's simply a slightly wrong formula?

Finally, the -12V value reads at -12.02V on nearly every reading, yet
'sensors' shows an ALARM for it.  The min/max ranges are set properly (and set
with sensors) and I've never seen the value stray outside the limits.  I
suppose it's possible it varies a lot between readings, but shouldn't I see
something eventually?  Even if the value just moves slightly from -12.02V?

If you can help me at all with these issues, I would be grateful.  I would
also like to get the K7S5A-HOWTO updated if I can resolve these issues (and if
the author is still around).  Many thanks.

--John Gruenenfelder    Research Assistant, Steward Observatory, U of Arizona
johng at
"This is the most fun I've had without being drenched in the blood
of my enemies!"
        --Sam of Sam & Max

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