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My cpu is burning it self if I dont put it powersave state. recently widget on the top of my screen says 800Mhz but I know it is 1.733Ghz behind. I feel it because temp. passes 80 celcius (176 Fahrenheit).

Temp. is another problem, but I want to issue that command!

nerkn@nerkn-laptop:/var/www/onyuz$ sudo echo -n powersave > /sys/devices/system/cpu/cpu1/cpufreq/scaling_governor

but it throws

bash: /sys/devices/system/cpu/cpu1/cpufreq/scaling_governor: Permission denied

I cant cry to say I'm super! Super user, no permission I know! Can any body suggest any thing?

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up vote 2 down vote accepted

I don't know what the heat problem is, but I can tell you why your command failed: the redirect is set up before sudo is run, so you try to redirect it to /sys/devices/system/cpu/cpu1/cpufreq/scaling_governor as a normal user while the permissions don't allow that.

You can make a shell executes the whole command, including redirect, as root like this:

sudo sh -c "echo -n powersave > /sys/devices/system/cpu/cpu1/cpufreq/scaling_governor"
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nerkn@nerkn-laptop:/$ sudo echo powersave > /sys/devices/system/cpu/cpu1 bash: /sys/devices/system/cpu/cpu1: Is a directory – nerkn Oct 30 '10 at 23:13
Ooops, I accidentally didn't copy the whole thing from your question, will fix that... – JanC Oct 30 '10 at 23:33

Which CPU do you have? 800MHz is normal for many CPUs, if the CPU runs in Idle Mode. The CPU Clock will be reduced.

To run this bash command you have to add the sudo command

sudo bash ...

But try the top command first to look if there is a task running at 100%

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