Instructions
Move the PlayStation 3 to a well-ventilated area and do not stack other items on top of it. The device generates heat while running games and keeping it enclosed will only cause the heat to build up faster. The device will shut off before it becomes damaged from operating temperatures that are too high.
Ensure you have a steady power connection and that the outlet is not overloaded. If there is insufficient power coming into the PlayStation 3, it will shut off periodically.
Contact Sony's technical support department to resolve the issue. If your PlayStation 3 is still under warranty, they will repair it for you free of charge. You can obtain local contact information by selecting your geographic area on the PlayStation Support website (see Resources).