I have run into heating issues on my ultrabook running Linux. Idling temperature for Win7 is ~45 C, while in Linux it is ~55 C.
Output of sensors
rohit@raijin ~ $ sensors
acpitz-virtual-0
Adapter: Virtual device
temp1: +52.0°C (crit = +99.0°C)
temp2: +29.8°C (crit = +99.0°C)
coretemp-isa-0000
Adapter: ISA adapter
Physical id 0: +55.0°C (high = +86.0°C, crit = +100.0°C)
Core 0: +54.0°C (high = +86.0°C, crit = +100.0°C)
Core 1: +55.0°C (high = +86.0°C, crit = +100.0°C)
Output of acpi
rohit@raijin ~ $ acpi -V
Battery 0: Full, 100%
Battery 0: design capacity 6100 mAh, last full capacity 6100 mAh = 100%
Adapter 0: on-line
Thermal 0: ok, 29.8 degrees C
Thermal 0: trip point 0 switches to mode critical at temperature 99.0 degrees C
Thermal 0: trip point 1 switches to mode passive at temperature 97.0 degrees C
Thermal 1: ok, 52.0 degrees C
Thermal 1: trip point 0 switches to mode critical at temperature 99.0 degrees C
Thermal 1: trip point 1 switches to mode active at temperature 71.0 degrees C
Thermal 1: trip point 2 switches to mode active at temperature 55.0 degrees C
Cooling 0: LCD 0 of 7
Cooling 1: Processor 0 of 10
Cooling 2: Processor 0 of 10
Cooling 3: Processor 0 of 10
Cooling 4: Processor 0 of 10
Cooling 5: Fan 1 of 1
Cooling 6: Fan 1 of 1
Cooling 7: Fan 1 of 1
Cooling 8: Fan 1 of 1
Cooling 9: Fan 0 of 1
Kernel
rohit@raijin ~ $ uname -a
Linux raijin 3.2.0-27-generic #43-Ubuntu SMP Fri Jul 6 14:25:57 UTC 2012 x86_64 x86_64 x86_64 GNU/Linux
As per this suggestion I modified the GRUB_CMDLINE_LINUX_DEFAULT in /etc/default/grub to include
i915.i915_enable_rc6=7 i915.i915_enable_fbc=1 i915.lvds_downclock=1 drm.vblankoffdelay=1
It didn't help much.
What I want to know is how is Thermal 1: trip point 2, as show in the ACPI output, set? For that is where my CPU cores are settling on idle.
And how can I bring my cores to ~45 C at idle?
