I've been having issues with my laptop overheating recently, in fact ever since loading fedora the cpu has run hot. According to CoreTemp when in windows my CPU idles at 56ºC ( i.e. I've logged into windows opened outlook and walked away) considering my AMD Desktop machine runs at 40ºC with two users logged and the CPU peaking at 100%, means that my laptop cooks. In Fedora I've found that the CPU actually Idles at around 70ºC which is a joke, it means that the fan is kicking out hot air causing my desk and everything around it to get proper hot - don't leave any chocolate bars near me!

I need to get some colleagues to run coretemp for a while to see if my laptop is broken or if it's normal for this model of latop to run hot; in the meantime I thought I'd post some tips on what I've done to cool my laptop down. I've managed to get Fedora to idle at around 58ºC which is much closer to my windows base-line.

CPUSpeed is a service/daemon which controls what the processor is doing, i.e. if you're not running a lot it scales down the processor to run slower and use less power, thus runs cooler. I found that my daemon was actually crashing at boot up....

#/etc/init.d/cpuspeed status
cpuspeed dead but subsys locked 
#

The config file for cpuspeed is /etc/sysconfig/cpuspeed, I've changed the govenor from blank (default: auto detect) to GOVERNOR=ondemand which seems to have solved my crashing issue. The second thing I've changed is IGNORE_NICE=1 (default: 0) which is now restricting which processes can scale up the CPU. The only performance impact I've seen is that this setting now stops VMWARE from consuming my CPU, and since I'm a patient man this is no bad thing :)

Whilst comparing my windows temp to my linux one it occurred to me that it wasn't entirely fair, in linux I've got compiz graphics enabled, and a load of gnome applets which tell me information about networking, cpu speed, cpu temperature, the weather etc.... since windows has none of these it's fair to say that my linux desktop should run a little hotter.... so the "other" trick I've done to bring the temperature down is to renice the applets to a lower priority...

ps ax | grep "applet" | grep -v grep|cut -c 1-5|xargs sudo renice 1

This seems to have done the trick, anything called "applet" now runs at nice 1 rather than 0, the net effect is these processes are queued up behind the "important" ones rather than continuously scaling up the processor.

I'm happy with the results so far, the desk is a lot cooler!