What is the 4th wire for on the processor fan?

什么是处理器风扇的第4线？

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The processor fan operates at a low speed while internal chassis temperatures are low.

当机箱内部温度低时，处理器风扇低速运行。

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Systems should be designed to provide air around the boxed processor fan heatsink that remains below the lower set point.

系统应该设计为使盒装处理器风扇散热器周围空气温度保持在设定点的下限以下。

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His recently completed Project Inverted, just highlighted by ASUS, puts most of the hardware on the outside: the Sabertooth Z77 motherboard, Core i5 processor, fan cooling, memory, Radeon HD 6870 video card and watercooling pipes all sit in plain sight.

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The processor then hung too close to the fan, its heat causing a sensor to go off which automatically shut down the server.

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To maintain its sleek physique, Intel pairs the desktop-class Core processor at the heart with a laptop-style heatsink and fan.

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