If your xbox 360 has suffered from the 3 red rings of death fault then this guide will help you fix it for FREE.
Do NOT waste your money on the xclamp repair kits as they rarely work!
If your xbox is less than 3 years old then send it to microsoft as it is covered by warranty if not read on.
If you have worked on pc's before then this is easy - after all the xbox 360 is a mini pc in a smaller case!
The 3 red rings means general hardware fault (usually the cpu or gpu have overheated) in order to fix this problem you need to take the xbox apart, remove the motherboard then remove the heatsinks on the cpu/gpu
Both heatsinks outlined
Clean all the old thermal paste/pads off both the heatsinks and the cpu/gpu chips.
Cpu & Gpu outlined
Reapply a new thin layer of thermal paste (artic silver or similar), Reattach the heatsinks -DO NOT OVERTIGHTEN
Refit motherboard. Test.
There are endless videos/guides on the net if you get stuck - just type xbox360 fix in your search engine or email me(its against ebay rules to post the links here)