[ILUG] lm sensors..

[Niall O Broin]

On Thu, May 17, 2001 at 07:46:25PM +0100, John P. Looney wrote:

> root:/# sensors 
> w83781d-i2c-0-2d
> Adapter: SMBus PIIX4 adapter at 5000
> Algorithm: Non-I2C SMBus adapter
> VCore 1:   +1.77 V  (min =  +1.61 V, max =  +1.98 V)              
> VCore 2:   +1.47 V  (min =  +1.61 V, max =  +1.98 V)       ALARM  
> +3.3V:     +3.32 V  (min =  +2.97 V, max =  +3.63 V)              
> +5V:       +4.97 V  (min =  +4.50 V, max =  +5.48 V)              
> +12V:     +11.97 V  (min = +10.79 V, max = +13.11 V)              
> -12V:     -10.88 V  (min = -10.78 V, max = -13.18 V)              
> -5V:       -4.70 V  (min =  -4.50 V, max =  -5.48 V)              
> Fan #1:      0 RPM  (min = 3000 RPM, div = 2)              ALARM  
> Fan #2:      0 RPM  (min = 3000 RPM, div = 2)              ALARM  
> Fan #3:      0 RPM  (min = 3000 RPM, div = 2)              ALARM  
> Temp 1:   +31.0°C   (limit = +60°C, hysteresis = +50°C)        
> Temp 2:   +31.0°C   (limit = +60°C, hysteresis = +50°C)        
> Temp 3:   +13.0°C   (limit = +60°C, hysteresis = +50°C)        
> vid:      +1.80 V
> alarms:   Chassis intrusion detection                             
> beep_enable:
>           Sound alarm disabled
> 
>  I'm pretty sure that the processor should be running ~50C, and the case
> at least 25C. So, it looks like that's wrong. There seems to be some
> majick involved for calibrating it etc....but what ?

I did play with this once, but I've forgotten it all now - sorry :-)

However, the temperature sensors are usu. surface mounted on the board e.g.
under the processor so I would have though 31.0°C sounds reasonable esp.
given current ambient temperatures (you're not in Arizona  any more, John)
although 13.0°C would seem quite low.

However, I don't understand what they mean by 

(limit = +60°C, hysteresis = +50°C)

limit is understandable, but hysteresis ? I do know what hysteresis is, but
in this context ? In my ignorance, I would imagine that hysteresis in a
temperature sensor is a bad thing, especially of that magnitude. Obviously
I'm misunderstanding them, but what do they mean ?

>  I just snarfed this;
>     http://www.sauerland.de/~toyland/configs/sensors.conf.html
> and ran with it, and expected it to work. Mutter.

One thing to try is have the machine running a while so it's at its normal
temperature, then shut it down and quick as you can, get to the BIOS sensor
readings page and check what you see there for comparison with what sensors
reports.


Niall