I am using ubuntu 14.04 LTS on an i5-3250M, 6GB RAM Dell Inspiron laptop. I have been noticing all this time from my cpu usage monitor that there is high usage of my CPU (without using something really intensive) and it leads to overheating.
I checked from the system monitor, and at first it seemed like my graphics card was the problem (AMD Radeon 7670M - hybrid graphics with Intel HD 4000). Anyway, I installed fglrx-updates (the only one that actually kind of fixed the overheating problem - fglrx and xorg didn't help) and things ran a bit smoother.
I also installed intel p-state and thermald. Put it on powersave governor, but still no luck. Also installed tlp (no conflict between them).
Tried to see if the fault is from compiz or adobe-flash. No luck. Also, HTML5 uses a LOT of CPU after a bit and it lags everything on my comp.
After doing all of those, I was looking at the results from the $top command and the culprit seems to be kidle_inject. It uses like 50% of the cpu everytime. I couldn't help but notice that it seemed like it had four modules - kidle_inject/0 to kidle_inject/3.
So, what is this kidle_inject? I haven't been able to find something conclusive on the subject. It seems to be on when I use something that is resource intensive and it continues hogging my cpu for a minute or two after terminating usage.
How can I fix this so that my comp is usable at last? I am talking about a minimum temperature of 70C in low-performance use. I am heavily dependent on linux and I would like to keep using ubuntu (since I am used so much to it and I have grown fond of it).
-- I have to say that this is not my machine's fault. When it runs on Windows 7 it's running fantastic with low temperatures.