Symptoms :

Notebook work fine , and sometimes shutdown after only a few minutes ?
Unit shutdown/freeze when using intensive cpu apps ?
Fans sound louder than before, and running at high speed ?

If so it sounds like the cooling system is clogged up.

Here’s one of the tips, it shows pic’s of the cooling system, showing the cooling fins clogged which will cause a unit to overheat.

http://www.laptoprepairguy.com/lapto…p-overheating/
http://irisvista.com/tech/laptops/To…verheating.htm

Remember : Most all laptops on the market have the cooling intakes on the bottom of the unit which sucks in hair, dirt, dust , lint, etc and can clog the cooling system in a short amount of time…