Fan is always running and temperature is warmer than normal.

[sanjie]

Originally Posted by Sxooter

If you've got a 2nd gen core i CPU, it WILL RUN HOT for now. There was a nasty power usage regression in the 2.6.3x series kernels along the way, and since you can't get the earlier kernels to work well with modern sandybridge HW, you're stuck, for now, with the power usage regression.

This should be addressed in the next ubuntu release, 12.04 which I'm going to test on my spare SandyBridge laptop to see how it works to lower power usage on the CPU.

All distribution of Linux have this problem?

[SemiExpert]

Originally Posted by sanjie

All distribution of Linux have this problem?

Sometimes issues are kernel related and you need to wait for an updated kernel for the fix. We're coming up on linux 3.3, and there are supposed to be a number of power regression fixes.

[Sxooter]

yes, all current distros have this problem. you have to go back a year or more to get a kernel that doesn't have this issue.

The 3.3 kernel has the fixes for the power usage regression, and canonical is supposedly back porting them to the 3.2 kernel for 12.04. It looks like they're either not all in or only partially in. I tried a snapshot from last week on my spare sandybridge machine and went from 120 minutes to 141 minutes on battery. A gain, but I'm really hoping to go from 120 minutes to 240 minutes etc.

[sanjie]

Originally Posted by Sxooter

yes, all current distros have this problem. you have to go back a year or more to get a kernel that doesn't have this issue.

The 3.3 kernel has the fixes for the power usage regression, and canonical is supposedly back porting them to the 3.2 kernel for 12.04. It looks like they're either not all in or only partially in. I tried a snapshot from last week on my spare sandybridge machine and went from 120 minutes to 141 minutes on battery. A gain, but I'm really hoping to go from 120 minutes to 240 minutes etc.

So 10.04 would work fine?

[SemiExpert]

Originally Posted by sanjie

So 10.04 would work fine?

No, going back to an earlier version of the kernel might remove or degrade support for other aspecst of your system.

3.3-rc1 is already here, so you don't have to wait much longer.

[RWUK]

I've had bad luck with Ubuntu releases properly configuring themselves for CPU frequency scaling. The CPUs would sit at maximum clockspeed (got 2.4 Ghz C2D processor) until I changed the governor and settings in the governor located at /etc/cpufreqd.conf. This was on Mint 10 (Ubuntu 10.10) and I've not played with Ubuntu releases outside of VM's since then.

I think 11.10 comes with cpufrequtils so the command 'cpufreq-info' will tell you what your clockspeeds are for each core.

About the kernel power regression, I found this to be helpful
Ubuntu Forums - View Single Post - [ubuntu] Samsung series 9

[SemiExpert]

New Linux kernel fixes power-saving issues - The H Open Source: News and Features

[ThinkRob]

Originally Posted by SemiExpert

New Linux kernel fixes power-saving issues - The H Open Source: News and Features

The ASPM detection issue has virtually nothing to do with CPU temperature. It's good that we have a work-around for buggy BIOSs, but if you're expecting this to drop CPU temperatures tremendously I'm afraid you might be in for some disappointment. (Also, it's not a "regression". It's a fix for a behavior that crashed some machines with buggy BIOSs. It's being replaced by an even better implementation that happens to lower power usage in the process.)

I hate to ask the obvious, but since As far as I know it hasn't been answered: are you sure you don't have some process that's stuck burning up CPU time?