Little information is know about NVIDIA's next-gen graphics core, the G70. But it is said that it will use single slot cooling and that it won't get very hot.
NVIDIA definitely managed to get further then we expected. Remember, Nvidia changed its plans and cancelled some of its chips including NV50 in favour of G70. All bets are on the G70 now.
The G70 also won't have special power requirements. More info at The Inquirer
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