I wouldnt worry about it. A Sata cable basically is the data cable that connects your hardrive or a cd/dvd-writer to your motherboard. Most computers actually have a few extra so that you can just add another device to your computer, (for example a blu-ray dvd player). Most fans like that are connected to the motherboard, but if its working, then there is not a connectivity issue. Needless to say, some fans commonly malfunction, but others are actually controlled by the motherboard sensors that measure the heat within the case, when it gets hotter, then it will speed up, and if its nice and cool, it doesnt run as fast. Hope this helps!
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