The first shipment of Xbox 360's left the Microsoft assembly line with a few small, seemingly insignificant defects that were probably highly overlooked.
Thankfully Microsoft honored the warranty of their products and learned of the problem and subsequently made the necessary changes to ensure it wouldn't happen again.
Outside of your warranty you may need to do it yourself, so here's how to repair red ring of death using simple tools and materials you can get from your local hardware store.
Although the overall consensus of the error is that was caused by overheating, that it is a broad generalization for a number of smaller things that could cause overheating themselves.
To find them, first remove the shell and find the motherboard.
Turn it over and locate the two X-clamps which house the heat sink, as well as the CPU and the GPU.
Remove these three components carefully and clean them.
Debris from the manufacturing process would sometimes get into the heat sink and cause electrical flow disruption, which eventually resulted in the red ring error.
Apply a new thermal compound to the heat sink to be sure it is properly insulated.
It may also be wise to clean the processors too.
Reattach the clamps with new screws as the old ones were of low integrity and would erode from the temperature of the machine under normal conditions.
Replace the cover, and you should be done.
Sometimes, though, this isn't enough and in this case the problem is usually the graphics chip.
Under warranty, Microsoft would replace it for free, but with your warranty expired, you will have to replace it yourself.
The installation is easy enough, but the graphics card could cost you a pretty penny.
However, it's still cheaper and less hassle than replacing your whole xbox console.