[gentoo-user] Output of sensor "k10temp-pci-00c3"

[gentoo-user] Output of sensor "k10temp-pci-00c3"

[Sascha Cunz]

In the recent thread "system freezes during compiles", Carlos Henderson showed 
the output of $(sensors), among them the output of the k10temp-pci-00c3.

I stopped trusting that sensor. After some hours of idle, it shows me:

k10temp-pci-00c3
Adapter: PCI adapter
temp1:        +16.8°C  (high = +70.0°C)
                       (crit = +70.0°C, hyst = +67.0°C)

16.8°C is roughly 4°C _below_ the room temperature. If I'd boot to Windows 
right now, the mainboard-manufacturer's system utility shows a CPU temperature 
of 25°C (which is more or less the usual value it shows for Windows when 
idle).

My CPU is:

processor       : 5
vendor_id       : AuthenticAMD
cpu family      : 21
model           : 1
model name      : AMD FX(tm)-6200 Six-Core Processor             
stepping        : 2
microcode       : 0x6000626

running on an Asrock mainboard (Kernel is a gentoo-3.8.1-r1).

My question to the list is: Could this strange temperature be realistic? Does 
anyone have similar observations with AMD-Bulldozers?

Sascha

Re: [gentoo-user] Output of sensor "k10temp-pci-00c3"

[Carlos Hendson]

On Fri, 2013-03-22 at 20:58 +0100, Sascha Cunz wrote:
> In the recent thread "system freezes during compiles", Carlos Henderson showed 
> the output of $(sensors), among them the output of the k10temp-pci-00c3.
> 
> I stopped trusting that sensor. After some hours of idle, it shows me:
> 
> k10temp-pci-00c3
> Adapter: PCI adapter
> temp1:        +16.8°C  (high = +70.0°C)
>                        (crit = +70.0°C, hyst = +67.0°C)
> 
> 16.8°C is roughly 4°C _below_ the room temperature. If I'd boot to Windows 
> right now, the mainboard-manufacturer's system utility shows a CPU temperature 
> of 25°C (which is more or less the usual value it shows for Windows when 
> idle).
> 
> My CPU is:
> 
> processor       : 5
> vendor_id       : AuthenticAMD
> cpu family      : 21
> model           : 1
> model name      : AMD FX(tm)-6200 Six-Core Processor             
> stepping        : 2
> microcode       : 0x6000626
> 
> running on an Asrock mainboard (Kernel is a gentoo-3.8.1-r1).
> 
> My question to the list is: Could this strange temperature be realistic? Does 
> anyone have similar observations with AMD-Bulldozers?
> 
> Sascha
> 

Hi Sascha,

As a comparison, here's my machines processor:

vendor_id	: AuthenticAMD
cpu family	: 16
model		: 10
model name	: AMD Phenom(tm) II X6 1100T Processor
stepping	: 0
microcode	: 0x10000bf

From the kernel document hwmon/k10temp has a couple points:

1. The driver detects the mainboard socket type and not the processors
actual capabilities.  If an AM3 processor is on an AM2+ mainboard,
driver options may be required.

2. The temperature reported is relative to the point at which the system
must supply the maximum cooling for the processors specified maximum
case temperature and maximum thermal power dissipation.

It would appear that the temperature reported is quite possibly correct,
although not intuitive or easily verified as valid.

Hope that helps.

Regards,
Carlos