Com 226 comp trouble shooting II theory book
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| Week4 To Understand Startup Problems(Power Supply Unit) Power Supply The power supply is the silver box that is usually located in the rear right quarter of the enclosure. Ac enters the supply through the ac line cord, which is connected at the rear of the enclosure. A supply then produces a series of dc outputs that power the motherboard and drives. The importance of a power supply is easy enough to understand, but its implications for system integrity and expandability might not be as obvious. Power supplies sustain a great deal of electrical stress in normal everyday operation. The conversion of ac into dc results insubstantial heat, which is why so many power supplies are equipped with a cooling fan. Surges, spikes, and other anomalies that plague ac power distribution (especially in underdeveloped regions of the world) also find their way into PC power supplies, where damage can occur. The quality of a power supply’s design and components and design dictate how long it will last in operation. A quality supply will resist power problems and tolerate the rigors of normal operation, but a substandard supply can fail spontaneously after only a few months of operation. When replacing or upgrading a power supply, be sure to choose a reliable model. Power supplies also limit a system’s expandability. Every element used in the PC requires a certain amount of power marked W for watts). The supply must be capable of producing enough power to adequately meet the system’s demand. An under-powered supply (typical in low-profile systems) or a supply overloaded by excessive expansion (which frequently occurs in tower systems) might not be able to support the power needs of the system. Inadequate power results in very strange system behavior such as unpredictable system lockups, random memory faults, or disk-access problems. When replacing a power supply, be certain that the new supply can provide at least as much power as the supply being replaced. When upgrading a supply, choose a supply that offers at least 50 watts more than the original supply. Download 1.89 Mb. Share with your friends:
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