Why My Computer is shutting down by itself?
It's Hot in There
Most likely this is an overheating situation. Itunes, RealPlayer, Windows Media player, etc. require a lot of processing power to decompress and decode music files, which can cause the system to get hot.
If your CPU is running at over 60 degrees you might be at risk of burning it out. Some systems shut down automatically when the temperature reaches an unsafe level.
Every few weeks I open my system unit and clean the fins on the heat sink that sits under the CPU. When they collect dust it restricts the airflow and prevents proper cooling. I just did that on my system and the CPU temperature dropped by ten degrees!
Download the free
Speedfan utility and it will tell you the temperature at which your CPU and hard drives are running.
Help, my memory is failing me!
If you determine that overheating is not the problem, the most likely suspect is bad memory. The best way to find the culprit is to pop open the system unit, remove (or replace) one RAM stick and see if the problem is solved. Run your system for a while and if the problem goes away, you win!
If not... lather, rinse and repeat for each RAM stick until you find the one that's misbehaving.