I had Windows 7 until yesterday, and then i wiped out my hard disc to install Ubuntu 11.10. But I've noticed that it overheats VERY quickly and gives you no reaction time and just switches off! similar to what would happen if you were to remove battery and unplug the power source! I had a similar problem when I was running the laptop on Windows 7 but that happened rarely. I have an HP Pavilion g6 which is less than a year old now. I want to know if theres any settings I can change or do anything that'll help me overcome this problem.
can you list your notebook specs? generally, it can be a problem with graphics hardware, cooling system(fan), or bios. check hp website whether your model has any available bios updates. one major reason of overheating, normally overlooked, is cleaning of notebook's cooling system. i faced same problem last year.