That's the question asked more by xbox 360 gamers, than any other. If you've owned an XBOX 360 over the last few years, then chances are great that you've run into the 3 red light error. Some estimates have the failure rate now at over 50%, which is just incredible.
So why does it happen?
Some people seem to think that it's an overheating problem. And while it is triggerred by an xbox that is too hot, that is not the main cause. The XBOX 360 should not have a 50% failure rate, no matter how long you play it.
After some research, I've found that it was in fact an engineering flaw in the production of the XBOX 360. To be specific there are 2 computer chips in the XBOX 360 (the CPU and the GPU) that are at the heart of this failure.
So what causes the 3 red light error? It is an elecrical connection failure between the main computer chip (the cpu, or gpu) and the mother board. So when an XBOXer plays his xbox for too long, or doesn't allow for cooling ventalation, the solder connection heats up, becomes soft, and often times will then crack or pull apart. This causes an electrical failure - and the 3 Red Light error will occur.