A silent cooling fan is a device that is installed within computer systems to expel heat away from the core components. It can be used to bring fresh air into the case or to push hot air out of it, and many systems implement a series of silent cooling fans that move air in both directions. When installed properly, a silent cooling fan uses very little power and creates little to no noise while in operation. Some models can also be calibrated with special software that has them activate the fans when the system begins to overheat.
Many people fail to realize that the number one threat to any computer system is overheating. The average processor runs so hot that it could actually boil water if the heat was not quickly dispersed in some fashion. The attached heatsink can only release heat into the computer case. Within minutes without some kind of cooling fan installed, the memory, video card, and eventually the motherboard could overheat and cause irreversible damage. By using a silent cooling fan keeping the interior air in constant motion, the overall temperature can be kept within tolerable levels.
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The most common sizes of silent cooling fans are 3.14 and 4.72 inches (80 and 120 millimeters), but they are also available in a variety of different sizes. Consumers wishing to install a primary silent cooling fan should measure the distance between the pre-cut mounting holes within the system. They are normally located on the back of the computer case, on the side, or directly above the processor. Once a silent cooling fan is purchased, it can be attached with four screws, and the cord needs to be plugged in to the power supply. Most fans spin clockwise when their blades are slanted to the right, and they are also fully reversible.
Some users will also download a software application that will control each of the silent cooling fan units within the system. After the program is calibrated, it monitors critical areas of the system and controls each of the fans accordingly to keep power consumption and heat buildup to a minimum. If the memory was getting too hot, for example, the software would temporarily increase each of the silent cooling fans up to 200% of their recommended speed to expel the heat away from that area quickly. Likewise, when the system is running cool, it would considerably slow the fans down or temporarily disable them.