# Windows is cooler than linux (literally)

## misc

Hello, I have an inspiron 5150 notebook and Linux runs about 20C hotter than what XP does. So, when both idle, windows runs at around 35 while linux runs at about 55C. 

Anyone else notice this? This is while the fan is the same speed in both linux and windows - its still 20C hotter even when not running X.

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## ChopChopMasterOnion

haven't noticed anything of the kind on my Thinkpad 600E, but it's a fair sight older.  I wonder if it's something to do with kernel power management.  Most of my throttle and fan are crontrolled by my BIOS though, as best as I can tell.

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## misc

Hmmm not sure... maybe

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## Athas

When you compile the kernel, you can toggle on a lot of power-management-features (especially CPU-scaling is relevant), you should try that.

By the way, isn't 55 degrees C a bit too much for a notebook   :Shocked: 

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## misc

Nah I've already got all that turned on (including CPU-scaling).

And 55C is lovely for a laptop, well for me it is anyway! It has been idling at about 70C for god only knows how long (few months maybe?) - I only got my acpi working properly yesterday and noticed it waaaaay too high, so I opend up a can of whoop ass on it (compressed air I mean) and it made a world of difference.   :Smile: 

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## garn

even if cpu scaling is on in the kernel you need a daemon to make use of it, like powernowd (works on non-"powernow" cpus too)

and 70C? That's REALLY hot. My top is always less than 30C.

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## feystorm

my laptop used to run extremely hot while in linux too, my cpu fan never shut off, it was always running at full speed. then i downloaded a new version of acpi and the kacpid patch. the acpi version that was in the kernel didnt work properly, like kernel 2.4.19 or 20 or something. and the kacpid patch was because some laptops are a bit screwed up and lost the acpi interrupt, and acpi wouldnt work. but on kernel 2.4.21 and 2.4.22 it worked fine, without those patches, perhaps the patches were included in the kernel...

but with proper acpi support, my fan sometimes went completely off, even in X and with mozilla running.

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## misc

Ohhh ok, well mine runs at about 55C pretty much all the time, like now, I have Mozilla with about 10 tabs, 10 Eterms, evolution, amsn, xchat, etc, and its still on 55C. So thats not too bad, but with Windows it does idle a lot cooler. 

I'm using 2.6.2 so I would think that the acpi would be working fine. Windows uses APM though I think? Maybe I should try APM rather than ACPI. Might look at powernowd as well, see if that makes a diff.

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## hanzotutu

```

scimd THM # cat temperature 

temperature:             40 C

scimd THM # pwd

/proc/acpi/thermal_zone/THM

scimd THM # 

```

AC adapter plugged in, so speedfreq uses performace.

If I switch it to powersave, the temperature should be lower.

BTW, my laptop is a Dell D600 with P-M 1.4G

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## BradB

My Toshiba Satellite 2410 used to run at 60-70C (fan off at 60, off at 70) it was a BIOS setting (battery save from memory).  I needed to replace my mainboard, I suspect it was too hot for too long.  Now I run between 50-55, (performance fan setting), much nicer.  I only way I could get that cooler would be to have the fan on all the time.

Brad

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## GaMMa

My laptop runs really hot too. Before I was averaging around 60 to 70C, now with speedstepping disabled in the BIOS I get around 40 to 60. Anyone have any idea why laptops are running so hot in Linux? Can't hot temperatures really damage the system? Are you sure that ACPI reading is accurate? I'm starting to doubt it..

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## mlsfit138

Is my athlon 1.1 (according to all diagnostics in all OS's I've ever tried it seems to run at 1.3ghz) capable of cpu scaling?  I'm always interested in conserving energy.  :Smile: 

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