The Swamp!

Just like any other machine, your computer may suffer from overheating.

Overheating occurs when:

1. Your CPU heatsink is blocked with dust, not allowing any airflow through it.
2. Your CPU fan is bad/broken. A decent CPU Fan shouldnt drop below 2000 rpm.
3. Your computer's environment is very hot (Closed non-ACed room, hot countries etc..)

We have a few recommendations for you, on how you may help your computer pass the summer safely by using cheap, widely available components.

Do not worry about animals in the house, your pets are smarter then that and will not fiddle-in with the insides of your computer, or they will once and learn the lesson.

Now, examine your CPU area.  the CPU sits right under the big fan thats attached to a wierd rounded or rectangular metal heatsink. if this looks like a big pile of dust, it needs cleaning:

1. Disconnect your computer from power.
2. Use a vacum cleaner (will require a strong one) or air pressure from a compressing device, or just get one of those cheap compressed-air sprays, those are good and last long.
3. Once the fan and heatsink are clean, this might already make the differance.

Leave the left cover open. 

Get one of those cheap 10" home-electric powered fans,  and make it stand right to the side of your computer, at full speed, this will help the airflow and will mix the hot air inside with a fresh, cooler air.

If your computer is very dusty on the inside, it is good to periodically clean it with air pressure or by hand using any kind of a thin brush.

If you're using a rough one, like a toothbrush, be carefull on the tiny circuits, it is better to use a softer brush.

Do all these, and you will save hundreads of dollars on computer parts and hours of efforts running back and forth to the nearest computer store.

Happy Summer :)