by 
After installing Ubuntu on my legacy laptop, i noticed that the CPU frequency is scaling down to 800 Mhz. (upon to the temperature i guess)
derya@dsezenlinux:~$ cat /proc/cpuinfo
processor : 0
vendor_id : GenuineIntel
cpu family : 6
model : 23
model name : Intel(R) Core(TM)2 Duo CPU T9300 @ 2.50GHz
stepping : 6
microcode : 0x607
cpu MHz : 800.000
When it is 800 Mhz. the computer becomes extremely slow, so i decided to keep it stabile at 2500 Mhz.
Steps:
1. Install cpufreq-selector
For Ubuntu, this is under gnome-applets pack:
sudo apt-get install gnome-applets
2. Run the following for each core:
sudo cpufreq-selector -c 0 -g performance
sudo cpufreq-selector -c 1 -g performance
3. Check if it is ok:
cat /proc/cpuinfo
