Instructions
Power up the Xbox 360 console, insert a game disc, and then turn on your television to determine if the red lights are still flashing. Note the error code number on your screen that accompanies the red ring. Remove all clutter surrounding the console and, if possible, move the console away from any adjacent obstructions, such as your TV monitor or a wall.
Turn off the system, allow it to cool for a few minutes, and then reboot it to check for the flashing red lights. If none are present, your Xbox is now well ventilated, and you shouldn't see the same flashing lights appear again (as long as you keep the area clear). If the Xbox is flashing red in three of the four quadrants (Q2 in the upper right remains blank), there's a hardware failure. Look at your TV screen and note if Error 74 is displayed.
Log on to the Xbox support site and have your Live ID and the console's serial number ready. Consult the paperwork included with your Xbox to determine if your Box is still under warranty. Error 74 means there's a hardware problem resulting from the building process, so if you're console is still under warranty or Error 74 is displayed, the console can be repaired free of cost. Follow the prompts on the site to register your console for repair.
Unplug the audio/visual (AV) connectors from both the Xbox and your TV if you have all four quadrants flashing red, an indicator that the AV cable is malfunctioning. Reconnect the cable or plug a new AV cable in to rectify the problem.
Unplug the console from the outlet should you see three of the four quadrants flashing, an indicator that something's amiss with the console's power supply. Plug the power supply into another outlet and check the small light on the supply: A red light (or no light) means the supply is bad. Purchase a new power supply to get the unit working again.