By bobp on Mar 18, 2009
It took approximately 15 months for the event to occur, but as it has happened to so many others the RROD was not unexpected. My son creates lots of computations on his 1 teraflop Xbox 360. Needless to say the gaming community is not very amused with Xbox 360 technical problems. More about community in a future post.
The console in our house suffered from the lower right quadrant ring of red light, otherwise known as the "E74 System Error." Microsoft has extended the 1-year warranty to 3 years for the RROD error, but the E74 System Error still only carries a 1 year warranty. It is becoming obvious that the common hardware failures are interrelated (heat and cold solder joints) but go figure.
Next came the big decision. Pack up the Xbox and ship it for a costly repair that will take 1 month or do it myself? There is plenty of information out there in the cloud as to how one can fix the problems that statistically should occur at a much lower percentage. My soon to be 15 year old son is contemplating a career in engineering so we said let's void the warranty that has already expired and see what happens...
To attempt a fix you need to disassemble the whole unit down to the bare motherboard. This includes opening the clever injection molded plastic case that has no screws, the metal case that requires Torx screwdrivers, the control PCB that drives the (see picture above) on/off LED button, the CD drive, the air plenum, the heatsinks, the dual cooling fans, the drive power cable and the drive data cable. Next you need to unscrew the motherboard from the metal case in order to expose the back of the motherboard. Here is where the infamous x-clamps reside. You need to remove the x-clamps that secure the heatsinks to the 2 custom ASICs. The 2 ASICs are pretty impressive. A custom multi threaded (2) multi-core (3) IBM PowerPC-based CPU and a custom ATI GPU. Polygon performance is 500 million triangles/sec and 48 billion shader operations/sec. No wonder the HPC community is programming GPUs for their computational might. 512 MB of 700 MHz GDDR3 RAM feeds the GPU. Memory interface bandwidth comes in at 22.4GB/sec. Not bad at all but here lies the problem. The Xbox is a screaming number cruncher which produces electrical resistance and as a result heat. Thermal expansion (heat) and thermal contraction (cool) cause the motherboard to be bent by the x-clamps. Repeated cycles of this causes cold soder joints. One bad connection on a signal and your Xbox is toast. By the way server engineers have been dealing with this issue for years. The thermal problem can be solved, but it can and usually does as the result of adding cost to the product. In my opinion the issue for the Xbox is that it is an extremely high volume product and trading off added cost versus margin to a gaming console is a difficult balance.
The fix basically involves reflowing the solder balls in the CPU, GPU, RAM area with a heat gun. Assuming this is successful you have to put the whole game console back together. But before you do this you replace the x-clamps with metric screws to attach the heat sinks. You have to be very careful to clean the old heat paste completely from both ASICs before applying artic silver 5 thermal paste. If you do not do this correctly your heatsinks will not work efficiently and your unit will overheat quickly.
We put the whole thing back together and powered it up around 10:30pm after spending about 6 hours working and 2 trips to the hardware store and RadioShack . It worked! My son was happy as he was able to get to level 65 on Call of Duty 5.
I suggest that if you want to increase the odds of not getting RROD on your Xbox then mount your console in the tower position (standing on end) rather than flat like a laptop. When the console is in the flat position the motherboard is on the bottom of the unit and cooling is more difficult. When the console is mounted on it side (which is a valid position since it has skid pads on its side as well as bottom) the motherboard is cooled more efficiently. It's even better if you can can mount the Xbox on 4 small blocks so that more cool air can flow into the unit from all top, bottom and side intakes.
It was fun showing my son aspects of engineering in practice but even more enjoyable to actually have fixed the console for him. On the downside-- given the data out there on these RROD problems, I know the unit will ultimately fail again...
Blog is available also at: http://bobporras.wordpress.com/