On Sunday 12 June 2011 16:56:33 Pasi Kärkkäinen wrote:
Hello list,
Any tips how to debug why laptop CPU temperature is around 30 degrees
celsius higher on Fedora 14 or Fedora 15 compared to Windows 7 ? Both
Linux and Windows were idle when measuring..
I tried both Fedora 14 (Linux 2.6.35) and Fedora 15 (Linux 2.6.38).
Laptop specs:
- HP Elitebook 8530p.
- CPU: Mobile Intel Core 2 Duo T9600 (Penryn).
Results:
- Windows: CPU is 57 - 65 celsius when idle.
- Fedora/Linux: CPU is 85 - 95 celsius when idle.
The laptop definitely feels much more hot when in Linux
and sometimes shuts down with thermal overheating warning.
That overheating problem never happens in Windows.
Checking "powertop" in Linux shows the CPU is mostly running
with the lowest MHz available. Not much "idle" time though..
I was using "Core Temp" in Windows and /sys ACPI interface in Linux:
# cat /sys/bus/acpi/devices/LNXTHERM\:03/thermal_zone/temp
86000
# cat /sys/bus/acpi/devices/LNXTHERM\:03/path
\_TZ_.CPUZ
"acpi -t" also shows the same CPU temperature.
Fedora 15 Linux 2.6.38 dmesg here:
http://pasik.reaktio.net/fedora/f15/cputemp/dmesg-laptop-f15.txt
Any ideas how to track what's causing that? All suggestions welcome!
Thanks,
-- Pasi
What is the graphics card?
I am running this from a laptop of the same model and I see:
$ sensors
acpitz-virtual-0
Adapter: Virtual device
temp1: +30.0°C (crit = +115.0°C)
temp2: +50.0°C (crit = +105.0°C)
temp3: +26.6°C (crit = +112.0°C)
temp4: +58.0°C (crit = +112.0°C)
temp5: +46.0°C (crit = +90.0°C)
temp6: +16.0°C (crit = +112.0°C)
radeon-pci-0100
Adapter: PCI adapter
temp1: +58.0°C
coretemp-isa-0000
Adapter: ISA adapter
Core 0: +51.0°C (high = +105.0°C, crit = +105.0°C)
coretemp-isa-0001
Adapter: ISA adapter
Core 1: +50.0°C (high = +105.0°C, crit = +105.0°C)
The only thing I have done in order to cool down graphics card was to run:
# echo mid > /sys/class/drm/card0/device/power_profile
instead of the default value auto (that alternates between mid (middle) and
high) for the graphics card.
Definitivily I saw an improvement between F14 and F15.
Running the graphics card power profile as low brings the temperature even
lower (at the expense of some slower window updates).
FWIW I never had a problem with overheating.
Regarding the comparison with windows (win.. what?) ;-) this computer came
with freedos installed so no such luck here. :-D
--
José Abílio