# sensors work, but what does it mean?

## SerfurJ

where can i find documentation that will help me make sense of all this?

```
# sensors

it87-isa-0290

Adapter: ISA adapter

VCore 1:   +1.66 V  (min =  +1.42 V, max =  +1.57 V)   ALARM

VCore 2:   +2.51 V  (min =  +2.40 V, max =  +2.61 V)   

+3.3V:     +3.26 V  (min =  +3.14 V, max =  +3.46 V)   

+5V:       +4.92 V  (min =  +4.76 V, max =  +5.24 V)   

+12V:     +12.42 V  (min = +11.39 V, max = +12.61 V)   

-12V:     -14.84 V  (min = -12.63 V, max = -11.41 V)   ALARM

-5V:       -9.69 V  (min =  -5.26 V, max =  -4.77 V)   ALARM

Stdby:     +5.03 V  (min =  +4.76 V, max =  +5.24 V)   

VBat:      +0.00 V

fan1:        0 RPM  (min =    0 RPM, div = 4)          

fan2:        0 RPM  (min = 2657 RPM, div = 2)          ALARM

fan3:     4066 RPM  (min = 2657 RPM, div = 2)          

M/B Temp:    +38 C  (low  =   +15 C, high =   +40 C)   sensor = thermistor   

CPU Temp:    +49 C  (low  =   +15 C, high =   +45 C)   sensor = thermistor   

Temp3:       -55 C  (low  =   +15 C, high =   +45 C)   sensor = thermistor   

```

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## magoseitor

SerfurJ, what exactly you don't understand in that?

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## SerfurJ

what is the significance of the different voltages, why they would be changing, and what is a normal range.

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## LynZ

Hey.. have you ever watched your pc-health status in Bios?

These are exectly the same sensors.

The thing is that your motherboard is powered by several different voltages.

The normal values are in the names of the sensors.

Why are they changing? How do you think is tha possible to get EXACTLY the required voltage? That simply almost impossible according to some simple physical laws. =)))

So the fluctuate near the required value. just don't take that seriosly.. it is OK.

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## SerfurJ

yes, i've seen that in BIOS, but i've never understood why i'd want to be watching them.  that's my question: why would the voltages need to be monitored?  overclocking is the only situation i can think of.

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## freelight

If the voltages are considerably off, you might get system instability and/or fry something. This would happen due to overclocking, or a poor/failing power supply. (This is why investing in a good, reliable power supply is very important. Never skimp out on the power supply when building a system.)

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## magoseitor

SerfurJ, the better your voltages are, the happier your CPU is.

Normally the diference (minimal) is noticed when overclocking or putting under hard-task your cpu, also, higher voltages means higher-than-normal temperature, thats also why you should keep each voltage rail straight as possible...

conclusion, main reason why good voltages are always good and (deserve) to be monitored...

-->more stable CPU

-->more MTBF time for your CPU

-->better temperatures and less electromigration (wich result is the before one)

greets..  :Wink: 

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## SerfurJ

thanks for the explanations.  the only voltage that i'm worried about is the -5V.  it's -9.69V.  what can be done?

here's the full output of sensors:

```
it87-isa-0290

Adapter: ISA adapter

VCore 1:   +1.66 V  (min =  +1.42 V, max =  +1.57 V)   ALARM

VCore 2:   +2.51 V  (min =  +2.40 V, max =  +2.61 V)   

+3.3V:     +3.26 V  (min =  +3.14 V, max =  +3.46 V)   

+5V:       +4.92 V  (min =  +4.76 V, max =  +5.24 V)   

+12V:     +12.35 V  (min = +11.39 V, max = +12.61 V)   

-12V:     -14.84 V  (min = -12.63 V, max = -11.41 V)   ALARM

-5V:       -9.69 V  (min =  -5.26 V, max =  -4.77 V)   ALARM

Stdby:     +5.00 V  (min =  +4.76 V, max =  +5.24 V)   

VBat:      +0.00 V

fan1:        0 RPM  (min =    0 RPM, div = 4)          

fan2:        0 RPM  (min = 2657 RPM, div = 2)          ALARM

fan3:     4066 RPM  (min = 2657 RPM, div = 2)          

M/B Temp:    +38 C  (low  =   +15 C, high =   +40 C)   sensor = thermistor   

CPU Temp:    +49 C  (low  =   +15 C, high =   +45 C)   sensor = thermistor   

Temp3:       -55 C  (low  =   +15 C, high =   +45 C)   sensor = thermistor   

```

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## magoseitor

well, i am not sure about that -5V, i have personally never paid attention to the negative rails, but it should be done...

My sensors don't even show the -5V rail, but the -12V one has the same values as yours, and i can asure my PSU is top notch so don't worry to much....

In last case if you want, grab a multimeter and measure the voltages from the PSU and from the motherboard just to make very sure all is ok.

 :Wink: 

PD:here are my stats..

```

w83627thf-isa-0290

Adapter: ISA adapter

VCore:     +2.76 V  (min =  +0.01 V, max =  +0.01 V)

+12V:     +12.36 V  (min = +10.84 V, max = +13.21 V)

+3.3V:     +3.29 V  (min =  +3.14 V, max =  +3.48 V)

+5V:       +5.18 V  (min =  +4.75 V, max =  +5.26 V)

-12V:     -14.88 V  (min = -10.77 V, max = -13.16 V)

V5SB:      +5.06 V  (min =  +4.77 V, max =  +5.25 V)

VBat:      +3.33 V  (min =  +2.41 V, max =  +3.60 V)

fan1:        0 RPM  (min =  241 RPM, div = 32)

CPU Fan:  2710 RPM  (min = 6308 RPM, div = 2)

fan3:        0 RPM  (min =  117 RPM, div = 64)

M/B Temp:    +32 C  (high =  +117 C, hyst =    +8 C)   sensor = PII/Celeron diode

CPU Temp:  +35.5 C  (high =   +63 C, hyst =   +58 C)   sensor = PII/Celeron diode

temp3:     -48.0 C  (high =   +80 C, hyst =   +75 C)   sensor = PII/Celeron diode

vid:      +0.000 V

alarms:

beep_enable:

          Sound alarm enabled

```

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## SerfurJ

i think i'll short something out if i try to measure it with a multimeter.  i guess it's okay based on your stats.  thanks.

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## SerfurJ

i found a good summary:

http://www.pcguide.com/ref/cpu/char/powerSupport-c.html

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## magoseitor

yeah, interesting....maybe i'll use that special "K6 voltage stuff" to try to fix an old motherbord...

ce ya  :Wink: 

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