[intro]New, cooler Xbox 360 surfaces[/intro]
It's all about nanometers - the fewer the better. At the moment, most Xbox 360 CPUs are made to a 90nm spec. The nanometer measurement is the average size of the smallest features on the chips (in billionths of a metre). Smaller is better, because it takes less power and less time for the electronic pulses to fizz around the chips. That in turn means that chips with lower nanometer measurements can run at higher speeds and/or lower temperatures.
So why the science lesson? Because Microsoft is now shipping Xbox 360 consoles with new, 65nm chips. The Halo 3 special edition models seem to be the first to benefit. When these new chips are set to run at the standard clock speed, their improved efficiency means they operate at lower temperatures. This is good news, as it's another step towards eradicating the dreaded "Ring of Death" experienced by so many 360 gamers, where the Ring of Light turns red, signalling a malfunction caused by the chips overheating and in some cases breaking free from the motherboard.
These new chips will filter through to the whole Xbox 360 range in time, although at the moment there's no way of telling whether a new Xbox 360 is driven by the old or new chips, and it's highly unlikely that any official indication will be given by Microsoft. After all, they won't want to be left with a pile of 'old' 360s that nobody wants.