AIBS(4) 						   BSD Kernel Interfaces Manual 						   AIBS(4)

NAME

     aibs -- ASUSTeK AI Booster voltage, temperature, and fan sensor

SYNOPSIS

     aibs* at acpi?

DESCRIPTION

     The aibs driver provides support for voltage, temperature, and fan sensors available as an ACPI device on ASUSTeK motherboards.  The number
     of sensors of each type, as well as the description of each sensor, varies according to the motherboard.

     The driver supports an arbitrary set of sensors, provides descriptions regarding what each sensor is used for, and reports whether each sen-
     sor is within the specifications as defined by the motherboard manufacturer through ACPI.

     The aibs driver supports envsys(4) sensor states as follows:

     o	 Voltage sensors can have a state of 'valid', 'critunder', or 'critover'; temperature sensors can have a state of 'valid', 'warnover',
	 'critover', or 'invalid'; and fan sensors can have a state of 'valid', 'warnunder', or 'warnover'.

     o	 Temperature sensors that have a reading of 0 are marked 'invalid', whereas all other sensors are always assumed valid.

     o	 Voltage sensors have a lower and an upper limit, 'critunder' and 'critover', temperature sensors have two upper limits, 'warnover' and
	 'critover', whereas fan sensors may either have only the lower limit 'warnunder', or, depending on the vendor's ACPI implementation, one
	 lower and one upper limit, 'warnunder' and 'warnover'.

     Sensor values and limits are made available through the envsys(4) interface, and can be monitored with envstat(8).  For example, on an ASUS
     V3-P5G965 barebone:

       $ envstat -d aibs0
			    Current  CritMax  WarnMax  WarnMin	CritMin Unit
	   Vcore Voltage:     1.152    1.600			  0.850    V
	    +3.3 Voltage:     3.312    3.630			  2.970    V
	      +5 Voltage:     5.017    5.500			  4.500    V
	     +12 Voltage:    12.302   13.800			 10.200    V
	 CPU Temperature:    27.000   95.000   80.000			degC
	  MB Temperature:    58.000   95.000   60.000			degC
	   CPU FAN Speed:	878		 7200	   600		 RPM
       CHASSIS FAN Speed:	  0		 7200	   700		 RPM

     Generally, sensors provided by the aibs driver may also be supported by a variety of other drivers, such as lm(4) or itesio(4).  The precise
     collection of aibs sensors is comprised of the sensors specifically utilised in the motherboard design, which may be supported through a com-
     bination of one or more physical hardware monitoring chips.

     The aibs driver, however, provides the following advantages when compared to the native hardware monitoring drivers:

     o	 Sensor values from aibs are expected to be more reliable.  For example, voltage sensors in many hardware monitoring chips can only sense
	 voltage from 0 to 2 or 4 volts, and the excessive voltage is removed by the resistors, which may vary with the motherboard and with the
	 voltage that is being sensed.	In aibs, the required resistor factors are provided by the motherboard manufacturer through ACPI; in the
	 native drivers, the resistor factors are encoded into the driver based on the chip manufacturer's recommendations.  In essence, sensor
	 values from aibs are very likely to be identical to the readings from the Hardware Monitor screen in the BIOS.

     o	 Sensor descriptions from aibs are more likely to match the markings on the motherboard.

     o	 Sensor states are supported by aibs.  The state is reported based on the acceptable range of values for each individual sensor as sug-
	 gested by the motherboard manufacturer.  For example, the threshold for the CPU temperature sensor is likely to be significantly higher
	 than that for the chassis temperature sensor.

     o	 Support for newer chips in aibs.  Newer chips may miss a native driver, but should be supported through aibs regardless.

     As a result, sensor readings from the actual native hardware monitoring drivers are redundant when aibs is present, and may be ignored as
     appropriate.  Whereas on some supported operating systems the native drivers may have to be specifically disabled should their presence be
     judged unnecessary, on others the drivers like lm(4) are not probed provided that acpi(4) is configured and the system potentially supports
     the hardware monitoring chip through ACPI.

SEE ALSO

     acpi(4), envsys(4), envstat(8)

HISTORY

     The aibs driver first appeared in OpenBSD 4.7, DragonFly 2.4.1 and NetBSD 6.0.  An earlier version of the driver, named aiboost, first
     appeared in FreeBSD 7.0 and NetBSD 5.0.

AUTHORS

     The aibs driver was written for OpenBSD, DragonFly BSD, and NetBSD by Constantine A. Murenin <http://cnst.su/>, Raouf Boutaba Research Group,
     David R. Cheriton School of Computer Science, University of Waterloo.  Jukka Ruohonen <jruohonen@iki.fi> later reworked and adjusted the
     driver to support new ASUSTeK motherboards.  The earlier version of the driver, aiboost, was written for FreeBSD by Takanori Watanabe and
     adapted to NetBSD by Juan Romero Pardines.

BSD
								   June 12, 2011							       BSD