I've been wanting to post my solution for some time, but was not sure how it will be received. Anyway, here I go:
Purchased a RROD Core system (Mfg Date: 9/2006) off eBay back in January of this year. It had several forms of the RROD 0102 and 0100 which are probably the most common and definitely the result of a cold solder joint on the GPU. This system was unopened so I knew what I had to work with.
After getting the system I spent literally days researching the best fix and I think I've found it but don't fool yourself into thinking there is a permanent fix.
This is not a fix-all for every 360 out there but should help with GPU related problems. I do have to warn you, my fix is ugly but it uses common sense and really works.
What NOT to do:
1. RAM heatsinks, they are useless. Simply put, the RAM does not get hot. Open your case and run your 360 for 10, 20, 60, 120 minutes. The RAM will be as cool to the touch as before you started your system.
2. Upgraded internal fans or the 12v fan mod. There are adjustments to make the fans work more efficiently but they are free and make use of the stock fans. Besides the problem is the GPU heat sink, not the fans.
3. DO NOT reflow your system with any kind of external heating device. Letting the 360 overheat itself works just as well and is far less dangerous. Think about it, a heat gun could damage more than just the GPU and CPU, the CAPs and RAM for instance and they are not the problem. Overheating the GPU and CPU using the system can only hurt those components and it won't, they are supposed to get hot, thus the heatsinks.
4. A simple X-clamp fix will do, Amazon or eBay. The complicated kits which claim to prevent the motherboard from warping are crap. Yes, the overheating and cooling of the GPU cause the motherboard to warp which flexes the solder joints and creates a cold solder joint, but the damage is already done. If you cool the GPU properly and not with a fancy X-clamp kit this problem goes away.
5. The penny fix. Again, the RAM does not overheat so this doesn't fix that non-issue. What it does do is flex your motherboard which may temporarily prevent the cold solder joint but bending a motherboard to fix a solder issue just sounds like a bad idea and you are not attacking the real issue.
What TO do:
OK, so most of the RROD issues out there are GPU related. Why? Well first gen systems had a heatsink 1/3 the size of the CPU heatsink even though today's games rely on both very heavily. When a PC game doesn't work, what are the two items you most likely need to upgrade? The 2nd gen 360's added a 3rd heatsink attached to the GPU heatsink but placed it in the front of the system away from the fans due to space issues. So how do you solve the warping of the motherboard and overheating of the GPU?
1. Purchase an X-clamp fix from Amazon or eBay, get the minimum parts you need but be sure to get a kit with Arctic Silver 5. The heatsink paste can be something else but Arctic Silver 5 is proven to be the best. Some kits attach the metal cage to the motherboard and the heatsink for improved stability, but I'm not convinced this is an issue once the GPU is cooled properly but, if the screws do not use the metal cage you may have to drill the cage to allow the screw heads to come through the cage so that the motherboard lays flat. You never want to bend a motherboard but that should be common sense. This step should run you between $10-20.
2. AirFlow Cables. Do a Google or eBay search. You could also modify the existing DVD drive cable but this is easier and only $15 or so. You need the space over the GPU for the next step and there are ways to make an external drive look cool. I said it would not be pretty.
3. Purchase a 2nd gen 360 CPU heatsink from eBay for $10 or so. Use this heatsink on the GPU so that the GPU and CPU are now cooled equally, well almost, see the next step.
4. At this point you should not have to purchase anything else, except duct tape if you do not have it. I used white since it looked nicer and a Cheez-It box.
a. Underneath the white fan shroud you need to separate the two fans airflow by extending the shroud right to the centre of both fans. This will equalize the air flow across both heatsinks.
b. Cut out the GPU side of the shroud and extend it using the duct tape and cardboard to mimic the airflow on the CPU side.
c. Extend the shroud over the top of both heatsinks. The 360 fans blow outward and pull heat away from the heatsinks. So, the larger heatsinks draw away more heat, more surface area improves the fans ability then cool the heatsink, and the larger shroud prevents heat build up within the 360 itself.
5. Cut out the grate covering the fans on the back of the 360. This will obviously improve airflow and thus system cooling and it is a free mod.
6. Finally, to fix the 0102 and 0100 error codes the first time and when they come back in the future. Unplug the system fans, maybe even add a switch to make this easier if you do not want to have to keep opening your system. Personally I never bothered putting mine back together. Turn the system on and leave it for about 15 minutes. It should turn to 2 rings of death but it does not have to. Once the 15 minutes are up turn the system off reconnect the system fan and turn the system back on. This is equivalent to the 3 towel fix, the system burn in after the X-clamp fix, and the heat gun fix but much simpler and you should be good for another month or so. If the 0102 and 0100 error codes come back. Do this step again.
If anyone is interested I can post pictures but the ideas explained here are not original and pictures can be found elsewhere. I'll also answer any questions/criticisms that people have.