I earlier posted an item on the forum on this subject, pointing out the most common cause for Laptop computers to overheat is lint clogging up the cooling vents. This lint buildup seriously reduces the flow of cooling air over the components within the laptop causing the internal temperature to rise significantly.
I currently have a Samsung R519 Laptop and yesterday I was finally moved to investigate the extremely hot air coming from the side vents.
Here is what I found.... http://i308.photobucket.com/albums/kk327/griz_101/Lint.jpg
This method is obviously not recommended for the inexperienced or non technical user - they can have the problem fixed professionally.
I used a small LED torch to peer into the side vent and saw lint on the far side of the cooling fins so tried using a regular paint brush [used to paint the walls in ones house] to dislodge the dust and lint by pushing the long bristles into the fin assembly. I did this first in the hope that opening up the laptop could be avoided - wrong! Having finally gained access to the laptop...... I found the fan and cooling system attached to the rear of the mother board so removed the fan assembly. The picture above is what I found. The disturbed lint was caused by the brush bristles when I poked them through from the other side of the cooling fins before the laptop was disassembled. Needless to say, a thin coating of lint completely covering the cooling fin opening certainly reduced the air flow allowing the internal temperature to rise. Removing this blockage restored the normal operating temperature.
Merely switching on ones laptop when in this condition will cause it to run hot regardless of what OS it uses.
As an aside, I also own an HP laptop which was allowed to run in a similar condition for a prolonged period of time. This excess heat damaged an internal component resulting in permanent vertical coloured lines on the LCD screen. A fix is more expensive than a new laptop - hence using a Samsung now. A little maintenance would have prevented the problem.
I hope the above is of some help to anyone with a similar overheating problem.