Heatgun heatgun heatgun. I wrote a detailed tutorial on my blog, so do read that if you want to fix a RRoD 360.
http://satoshimatrix.wordpress.com/2009/10/05/xbox-360-red-ring-of-death-repair/Let me explain a few of the more common fixes and why they aren't as good:
Towel trick - This is a simple trick people commonly use to attempt to reflow their solderballs and get their 360s working again. By wrapping the console in a thick towel plugging it in and leaving it on for a good while, the system will overheat so much that it will start to melt the solder. As common sense would suggest, this is a rather inefficient way of getting to the solder and runs the risk of an electrical fire.
X-clamp fix - The x-clamp is a device that works by clamping down on top of the GPU and causing it to work by sheer pressure alone. I don't think that it's a bad fix, but again it doesn't really solve the problem. Since the parts to do it are cheap, its worth buying but I've personally seen 360's red ring even after an x-clamp has been installed.
Penny fix - inferior x-clamp like fix.
new fan - many aftermarket fans increase airflow at the cost of noise levels. If you install a new fan, your system will run cooler but it will also be much louder. Still, not a bad idea. I have a Whisper max fan installed in my 360 and I've learned to live with its second speed noise levels.
Heatgun - Heatgunning your solder is the more direct and best way to fix your system. If you follow my tutorial, you can apply the amount of heat you need to just the specific spots you need it to without worrying about overheating any of your compactors and other motherboard components. The most important thing to keep in mind when heatgunning is to provide even heat to the affected area. Never just point the heatgun and keep it pointed in one spot for more than 5 seconds.
Hope this helps. best of luck to ya.l
