Some days ago I installed lm_sensors to check mainboard voltages,
temperatures and fan speed. sensors-detect has succesfully detected
the available sensors, but output of command sensors was not fully
correct with default configuration file. I was not able to find a
special configuration file for this motherboard, so I tried to adapt
the existing one. Here is the result of my work -- maybe it is useful
for someone.
# Sensors configuration file used by 'libsensors'
# sensors version 2.9.2 with libsensors version 2.9.2 (Gentoo Linux)
#
# This is an adapted version of the lm_sensors configuration file for
# ASUS A8N-SLI Premium motherboard (S. Salewski, 24-DEC-2005).
# The default configuration file (/etc/sensors.conf) gives a wrong value
# for -12V and labels for CPU- and M/B-Temperature were exchanged.
# Substitution of the original sensors.conf with this file results in
# an output of command sensors similar to
#
# it8712-isa-0290
# Adapter: ISA adapter
# VCore: +1.36 V (min = +1.01 V, max = +1.60 V)
# +3.3V: +3.26 V (min = +3.14 V, max = +3.47 V)
# +5V: +4.95 V (min = +4.76 V, max = +5.24 V)
# +12V: +11.97 V (min = +11.39 V, max = +12.61 V)
# -12V: -11.77 V (min = -12.68 V, max = -11.32 V)
# Stdby: +4.87 V (min = +4.76 V, max = +5.24 V)
# VBat: +3.09 V
# Fan1: 1205 RPM (min = 664 RPM, div = 8)
# Fan2: 0 RPM (min = 664 RPM, div = 8)
# Fan3: -1 RPM (min = 664 RPM, div = 8)
# CPU Temp: +41 C (low = +15 C, high = +55 C) sensor = thermistor
# M/B Temp: +37 C (low = +15 C, high = +45 C) sensor = thermistor
# Chipset Temp:+35 C (low = +15 C, high = +50 C) sensor = thermistor
# These values seems to be reasonable and are similar to the values
# displayed in BIOS, but may be wrong!
chip "it87-*" "it8712-*"
# Voltage monitors as advised in the It8705 data sheet
# VCore2 and -5V voltage is not available for ASUS A8N-SLI Premium
label in0 "VCore"
#label in1 "VCore 2"
label in2 "+3.3V"
label in3 "+5V"
label in4 "+12V"
label in5 "-12V"
#label in6 "-5V"
label in7 "Stdby"
label in8 "VBat"
# vid is monitored by IT8712, but this value is not very useful
# and reported value (0.8V) seems to be to low.
# Range of vid can be modified with commands like
# echo 90 > /sys/bus/i2c/devices/9191-0290/vrm
# but the following statement does not work.
# set vrm 90
# So we ignore vid, VCore2 and -5V value
ignore vid
ignore in1
ignore in6
# Compute +5 and +12 voltage as usual
compute in3 ((6.8/10)+1)*@ , @/((6.8/10)+1)
compute in4 ((30/10) +1)*@ , @/((30/10) +1)
# For this family of chips the negative voltage equation is different from
# the lm78. The chip uses two external resistor for scaling but one is
# tied to a positive reference voltage. See IT8712F_V0.8.2.pdf datasheet
# (www.ite.com.tw/product_info/file/pc/IT8712F_V0.8.2.pdf) page 91.
# Actual (displayed) voltage Vs depends of chip input voltage Vin:
# Vs = (1 + Rin/Rf) * Vin - (Rin/Rf) * Vref. (from datasheet)
# Vref = 4.096 V is chip reference voltage.
# If these two equations are correct, we can approximate the unknown
# quotient of voltage divider (resistors) Rin/Rf so that Vs=12 V.
# We can solve the above formula for Rin/Rf and use for Vin the value
# cat /sys/bus/i2c/devices/9191-0290/in5_input (2.960) or simple iterate
# until diplayed value is approximately -12 V.
# This results in Rin/Rf = 13.17, which we substitute in the above equation
compute in5 (14.17 * @) - 53.94 , (@ + 53.94) / 14.17
# Compute 5 V standby voltage as usual
compute in7 ((6.8/10)+1)*@ , @/((6.8/10)+1)
# Set tolerance for voltages. Message "Alarm" is displayed if outside.
set in0_min 1.0
set in0_max 1.6
#set in1_min 2.4
#set in1_max 2.6
set in2_min 3.3 * 0.95
set in2_max 3.3 * 1.05
set in3_min 5.0 * 0.95
set in3_max 5.0 * 1.05
set in4_min 12 * 0.95
set in4_max 12 * 1.05
set in5_max -12 * 0.95
set in5_min -12 * 1.05
#set in6_max -5 * 0.95
#set in6_min -5 * 1.05
set in7_min 5 * 0.95
set in7_max 5 * 1.05
#the chip does not support in8 min/max
# Temperature
# Sensor types: 2 = thermistor; 3 = thermal diode; 0 = unused
set sensor1 2
set sensor2 2
set sensor3 2
label temp1 "CPU Temp"
set temp1_over 55
set temp1_low 15
label temp2 "M/B Temp"
set temp2_over 45
set temp2_low 15
label temp3 "Chipset T"
set temp3_over 50
set temp3_low 15
# Temperature temp1 raises slowly with CPU load, temp3 raises very fast
# with load, temp3 changes very slowly and is higher than case temperature.
# Fans
label fan1 "Fan1"
label fan2 "Fan2"
label fan3 "Fan3"
set fan1_min 600
set fan2_min 600 # not connected for me
set fan3_min 600 # not connected for me
