Well the topic says it all. I have switched to debian gnu/linux and my engineering skills were tested. I faced troubles at almost every stage after installation. Let me describe the process.
I got myself a debian cd, put it in the cd - drive, restarted my laptop and after hitting the enter key about 10 times, debian was installed. I was greeted by a not-so-good-looking screen (clearlooks theme + gnome icon theme). I fired up iceweasel (debian's patched version of firefox (they are not allowed to call it firefox)). Within 5 minutes, my fan begins spinning. I realise that I am just running a web browser and reading a BOFH story. I check the output of cat /proc/acpi/thermal_zone/THRM/temperature. The output is 72 Degrees C. I am stunned. I close all applications and leave my laptop alone. Five minutes later, my laptop's fan is still spinning. I realize that something is surely wrong. I devise a plan. My first stop is to check how the fan's trip points. Trip points are basically the temperatures at which the behaviour or the system or the fan changes. I checked the output of "cat /proc/acpi/thermal_zone/THRM/trip_points". The output was:
critical (S5): 100 C passive: 92 C: tc1=2 tc2=3 tsp=100 devices=0xc124657c active: 73 C: devices=0xc12525a4 active: 66 C: devices=0xc1252694
So there you go. My fan would begin spinning when the cpu temperature hits 66 C. I decide to change the values a bit. I decide that it would be better if I set the values at boot-time and I add the following line to /etc/init.d/bootmisc.sh:
echo 90:0:62:52:50 > /proc/acpi/thermal_zone/THRM/trip_points
Upon booting, I check the trip points and I get:
critical (S5): 90 C passive: 62 C: tc1=2 tc2=3 tsp=100 devices=0xc124657c active: 52 C: devices=0xc12525a4 active: 50 C: devices=0xc1252694
It works! But just a few seconds later, the fan begins to spin. I check the temp again and: 63 C. "!@$@!#". What the bloody hell. The temperature kept shooting up and stayed put at 70 C. I shut my laptop down and open it up and armed with a cotton swab, I aim to clean up the buge amount of dust on the fan. Bad luck, there isn't any significant amount of dust there to cause a huge problem. I then realise that this route won't lead to a solution as well. I finally reboot my laptop with the aim of planning my next move. I run:
The output ensues and line 7 catches my eye:
cpu MHz: 1600
Bingo ! My genius brain figures out that cpu scaling is disabled. My cpu was running at 1600 MHz irrespective of the apps running. I know quite a bit about scaling as I had once asked people on IRC for help on overclocking my cpu. I was pointed to a tutorial about scaling then. I installed cpufrequtils and did:
modprobe acpi-cpufreq /etc/init.d/cpufrequtils restart
There is one issue however. While booting, debian complains that the OnDemand CPU failed. I was a bit irritated by this. But it was easy to figure out the solution. Plainly add modprobe acpi-cpufreq to /etc/init.d/cpufrequtils.