What is the cause of the red ring of death

A common cause of the "Red Ring Of Death" is the failure of the Nyko Intercooler inside the console. It has also been suggested that hardware failures can be caused by the fracturing of the solder used inside the console due to excessive heat and the wrong type of solder being used during construction. The top three causes are:
1) Overheating,
2) Problems in GPU,
3) Problems in powerbrick.
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