[SOLVED] CPU frequency scaling problems

[yaxattax]

Hi,

I've been trying for a while now to understand why my laptop CPU i5-2450M suffers from throttling after extended use at high frequencies. I am sure it is not thermal throttling, as sensors reports the CPU temp at around 65 degrees celcius. I also have my laptop plugged into AC, so I doubt total power usage is a concern, especially given that the CPU will turbo up to full speed ok, but slows down after 20-30 mins running at full speed.

I've tried changing the governor between perfrmance, ondemand, powersave and userspace (and poking highish values into the cpufreq files) but to no avail. I'm often seeing this

current CPU frequency is 1.60 GHz (asserted by call to hardware).

Also, although performance, etc, are available, I can only find references to ondemand:

[root@yaxattax-vse ~]# cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_available_governors
conservative userspace powersave ondemand performance
[root@yaxattax-vse ~]# ls /sys/devices/system/cpu/cpufreq/
ondemand
[root@yaxattax-vse ~]#

I really need to know how I can run my CPU at 2.5Ghz for extended periods of time.

Cheers,

Yax

[yaxattax]

Hi all,

Should have mentioned its a Sony Vaio SE. As it stands, what I believed about the STAMINA/SPEED switch not being listened to in Linux, it is incorrect. The switch is paid attention to, but more to my surprise it causes CPU throttling, which I was not aware of. This appears to be a design feature that occurs in Windows too, which isn't mentioned in the manual ...

Anyway, this is resolved.