Step 1: What causes the RROD?
Step 2: Why the towel fix works, but is bad
Step 3: So, how to fix it?
Step 4: Still fouling up?
Step 5: Reflow...
Step 6: Still Broken?!?!?!
Step 7: REBALL
Recall back to the beginning of this tuturiol when I described how chips now are using little balls of solder in place of contact pins (BGA afterall stands for Ball Grid Array). If you've ever soldered, you know that generally, there is a limit to how often and how much heat you can put solder through before it gets 'gunky' and doesn't flow, and no longer has that beautiful silver glint, but rather a pale, greyish coating. In these events, you generally replace the bad solder with new/good solder. Reballing is exactly that.
The process, in a nutshell, involves actually removing the chip from the board (gotta get it back up to 220+ degrees celsius again, and this time pull the chip off while solder is liquid). Once removed, you can use a combination of flux (to distribute heat more effectively), solder braid (absorbs melted solder in a ribbon of braided copper wires), and your soldering iron/pen to completely clean both surfaces (processor and board). Once clean, you apply a stencil with a bunch of holes to the chip (usually with bracket or rig of some sort), and then you can scoop almost microscopic beads of solder (might I suggest going with the LEADED solder this time, since the problems are most likely fault of lead-free solder?) into the holes in the stencil, heat the solder back to melting temp (around 220 again), and once set, remove the stencil leaving the balls melted in correct position to the processor. THEN you have to replace the chip on the board, and YET AGAIN bring it up to temp to melt the new solder to board (like reflow, this would just be a 'flow' I guess lol). Oh, yeah, you usually do this to the gpu AND cpu to cover your bases at minimum. You might do the ram too. Count on the reball kit running about $150 (includes stencils, balled solder, flux, and other tools). With this purchase, you could probably reball multiple processors (and that's about the only way to make this worth your while cost wise!). Video showing process is at http://www.youtube.com/watch?v=97nxZwHG5bA guy does it from start to finish (chip only) in about 10 min, but an amateur will probably take much longer.
Step 8: Working or pissed?
Like one guy says on that page about reballing, "There is no simple and cheap solutions for noobs!!!". I found a picture of the bottom of an Xbox GPU, counted the points, and there are exaclty 1,157 individual solder balls required to reball JUST THE GPU! The CPU appears to have more!
I hope you found this educational, or possibly helpful. There is literally probably over a dozen hours of reading forums, watching videos, scouring ebay, google, and other sites for components and processes to remove the mystery from the dreaded RROD. I hope this enables the brave souls out there to try their hand at reviving these great consoles!
Step 9: ***Update***
First unit I bought had seal broken, but was not registered with Microsoft. Expected delivery tomorrow, will see if they accept unit with an Ebay purchased seal replacing factory. While technically 'wrong' to do this, my justification is had Microsoft not produced an inferior product to begin with with almost 60% return rate, this wouldn't be an issue.
Second unit had seal broken and was registered. I baked in oven using instructions found at http://forums.llamma.com/viewtopic.php?f=25&t=27431 and was successful! Instead of all the garbage they used though, I simply used baby blankets that were destined for the trash/rag pile anyway. I wanted to be sure to use only natural fibers (don't want rayon/polyester melting to my board!), and masking tape to hold in place. The adhesive from the tape will be absorbed in the outer layers into the blankets, and my next attempt tonight will be done without the tape at all..
Third unit bought from Craigslist from a great kid going to college. Seal was never broken, and though it was registered to him, he helped by providing info so that Microsoft would transfer the unit to my account for submission. Unit was there 1 day before reported being shipped back, delivers tomorrow.
Fourth unit had no seal, powers up but with 3 flashing lights (?), looks like a beaver tried to chew its way into the case around holes in back. But, again, not registered! So, another seal purchased on Ebay, awaiting delivery of seal so I can ship it out (pending success of unit #1 that had to wait on seal as well).
Fifth unit just came today, haven't even opened, so going to tackle that now! Will take pics of my 'wrap job' and post here too!