Thanks for the guide. My brothers 8 year old xbox was getting 2 red leds after 10-15 minuets of playing. Further investigation showed that the CPU was overheating. I figured either the thing was clogged with dust, or the thermal paste was nonexistent, or both. Turned out it was both. I cleaned it out, removed what was left of the old thermal paste, and reapplied. The fans had been running at full speed for the longest time, but now its as if it just came out of the box.