CPU auto frequency scaling issue

[vh4x0r]

Hi,

This is my CPU on a Dell Inspiron laptop:

Code: Select all

% head -24 /proc/cpuinfo
processor	: 0
vendor_id	: GenuineIntel
cpu family	: 6
model		: 37
model name	: Intel(R) Core(TM) i3 CPU       M 330  @ 2.13GHz
stepping	: 2
cpu MHz		: 2133.000
cache size	: 3072 KB
physical id	: 0
siblings	: 4
core id		: 0
cpu cores	: 2
apicid		: 0
initial apicid	: 0
fpu		: yes
fpu_exception	: yes
cpuid level	: 11
wp		: yes
flags		: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx rdtscp lm constant_tsc arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc aperfmperf pni dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm sse4_1 sse4_2 popcnt lahf_lm arat dts tpr_shadow vnmi flexpriority ept vpid
bogomips	: 4256.80
clflush size	: 64
cache_alignment	: 64
address sizes	: 36 bits physical, 48 bits virtual
power management:

I have speedstep enabled in the BIOS, and acpi-cpufreq with performance, ondemand governors etc. work well. But, if the CPU temperature rises above 84C, the CPU automatically slows down to 933MHz, and completely ignores my cpufreq settings, and waits till the temperature falls below 60C. Something like this:

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if temp >= 85C :
  set speed 933MHz
  while temp >= 60C :
    sleep
    probe temp
  end while
  restore speed
end if

As a result of this, if I'm running some CPU intensive task (compiling, gaming), it takes forever to complete, and after that, the system takes a long time to cool down (since it's a laptop), so it feels very sluggish!

I agree with the choice of the value 85C, but the value 60C is too low, and I have to wait forever. What I would like to do, is to somehow adjust this value to say, 75C. I don't know whether this scaling setting is implemented somewhere in the firmware, or if there's a kernel option to tweak.

Does someone know of a solution or workaround for this issue ?

[the_mgt]

I think this is a BIOS issue. Did you set any "Critical Temperature" stuff in the BIOS? I guess this is a manufactures way of protecting the laptop from overheating damage.
I never had anything like this on any of the systems I owned.

[roarinelk]

This works as designed: it protects the processor from overheating.
Time to clean the heatsink and fan!