The dreaded Red Ring of Death (RROD) is an issue that plagued almost every first gen Xbox 360. Similar to the YLOD on the Ps3, this was generally caused by the system overheating too the point that the solder on the motherboard is damaged and prevents some components of the system from being able to make a connection and will trigger the 3 red rings to show up when you try to turn on the system. This video guide is really good and will show you how to repair the RROD on an Xbox 360.
Just like the fix for the YLOD on the PS3, the solution to fixing the RROD involved applying heat to the system’s motherboard in an attempt to heat the solder so that it will melt back into the connections that is should be in.
As the video mentions, there are lots of plastic components on the outer shell of the Xbox 360 that you need to remove carefully. If you are too rough you risk breaking some of the plastic parts outside of the system, so make sure to go slowly.
Some people suggest that you can use a hair dryer to do this. There are ways to do it using a hairdryer, but it poses a major fire risk and also runs the risk of irreparably damaging your Xbox. A heat gun is a completely different thing to a hair dryer and it gets considerably hotter. Use the tools shown in the video for best results.