[SOLVED] lm_sensors showing constant high temprature?

akamikeym · 09-06-2011, 05:26 AM

Hi,

I'm just trying out lm_sensors to monitor my sytem temp during use and I've noticed something odd. My it8720-isa-0228 (my motherboard temp moitor I believe) for temp3, I noticed was up at 80°C which seemed high. So I turned all my fan controls up (I've got a few manual ones) and all the other tempratures dropped by ~3°C bringing them down to not much above room temprature, but temp3 did not budge an inch. infact it has not moved a point of a degree while I've been monitoring it.

Is this sensor lying to me? How do I make sure?

Code:

Every 2.0s: sensors                                     Tue Sep  6 11:16:06 2011

k10temp-pci-00c3
Adapter: PCI adapter
temp1:        +32.0°C  (high = +70.0°C)
                       (crit = +79.0°C, hyst = +77.0°C)

it8720-isa-0228
Adapter: ISA adapter
in0:          +1.02 V  (min =  +0.00 V, max =  +4.08 V)
in1:          +1.52 V  (min =  +0.00 V, max =  +4.08 V)
in2:          +3.39 V  (min =  +0.00 V, max =  +4.08 V)
+5V:          +2.99 V  (min =  +0.00 V, max =  +4.08 V)
in4:          +3.10 V  (min =  +0.00 V, max =  +4.08 V)
in5:          +1.20 V  (min =  +0.00 V, max =  +4.08 V)
in6:          +3.39 V  (min =  +0.00 V, max =  +4.08 V)
5VSB:         +3.01 V  (min =  +0.00 V, max =  +4.08 V)
Vbat:         +3.17 V
fan1:        1415 RPM  (min =    0 RPM)
fan2:        1829 RPM  (min =    0 RPM)
fan3:        1229 RPM  (min =    0 RPM)
fan5:           0 RPM  (min =    0 RPM)
temp1:        +33.0°C  (low  = +127.0°C, high = +127.0°C)  sensor = thermistor
temp2:        +23.0°C  (low  = +127.0°C, high = +60.0°C)  sensor = thermal diode
temp3:        +80.0°C  (low  = +127.0°C, high = +127.0°C)  sensor = thermistor
cpu0_vid:    +1.250 V

akamikeym · 09-06-2011, 05:29 AM

UPDATE: Ok, it's now dropped to 79°C so I guess it's not lying to me. What on earth is it that's running so hot? How do I find out?

akamikeym · 09-06-2011, 07:09 AM

Well judging from my BIOS screen it can't be that important. Judging by similar Temperature reading from the BIOS screen Temp1 appears to be the Motherboard's reading form the CPU, Temp2 the system temperature and Temp3 is unlisted (I guess that means it's not that important). The only thing I can think of that could be running that hot is the PSU.

selfprogrammed · 09-09-2011, 02:17 PM

It is not necessarily connected to anything. Finding those temp sensors usually involves removing the motherboard and looking at it with a microscope to follow the traces from the port. Even then the things are usually under some big IC.

Try monitoring temp immediately from a cold start. If it is a real temp sensor, it should start at the same temp as the others, at least for a few seconds.

Otherwise, put an external temp measurement device on the likely IC and see which matches the
temp characteristics of the temp3. Use chiller spray to hit several candidate and watch temp3 for a response (just don't get carried away). Response can be around 2 to 10 seconds, so wait a while between tests.

Most likely, won't find anything that causes it to change.
A change of less than 2 degrees can be noise, conversion drift, or reference voltage drift.
Probably had a three port interface chip and only found reason to put two temp sensors on it (with the intention to use the third on their premium board).

sunnieside-up · 09-09-2011, 02:40 PM

I believe it could be the video card. If you have a generic driver installed, it will always keep your video at maximum clock, keeping it hot. You could install drivers from nvidia/ATI based on your card to fix this.