Chances of overheating?

[The Doctor]

Put it next to a fully open window elevated with it open.
Should be fine,BIOS will cut the power if it gets too hot AFAIK.

[prince of persia]

I wouldn't overclock a notebook since it has less space for air.

[igennie]

I think manufacturers have designed systems in such a way to handle such critical tasks...I won't recommend you to try anything like this..

[Loukas]

It's kinda risky. Anytime you leave your computer on all the time with programs running there are chances of it over heating.

[Telhast]

If you have to run it overnight , you need to take some necessary precautions .
1) Close all other unneeded programs and run only the program which is needed .
2) Keep your room cooled . An AC helps a lot when your laptop is directly under or in front of the AC's air flow .
3) Use a cooling pad , its really helpful .
4) Unplug your charger as soon as the battery is full . Then plug it in again if you need to later .
5) If you dont have a cooling pad , give your laptop a bit more lift to increase the airflow under the machine. Put a book or something of that sort under your battery .

On the contrary , if your laptop overheats , it will automatically shutdown to prevent damage to the hard drive and other components . This3emergency feature is available in almost all the laptops in this era .