This chapter is from the book
This chapter is from the book
This chapter is from the book
Heating and Cooling
Another issue to watch for is the system overheating. This can happen for several reasons:
Power supply fan failure
Auxiliary case fan failure
Inadequate number of fans
Missing or open slot covers
Case not being tightly closed and screwed in
Location of the computer
Air flow is important on today’s personal computers because their processors can often operate at hundreds of billions of instructions per second or more (referred to as 100 giga-instructions per second [GIPS]). They typically use 50 to 150 watts of power, and that creates a lot of heat! Add to that the video card and other cards that have their own on-board processors, and you quickly realize it can get hot inside the computer case. Plus, environmental factors and higher-temperature areas (such as warehouses and cafeterias) can cause heat to be trapped in the case, producing random shutdowns. Circulation is the key here. Air should flow in the case from the front and should be exhausted out the back. Any openings in the case or missing slot covers can cause circulation to diminish. If you have a computer that has a lot of devices, does a lot of processing, or runs hot for any other reason, your best bet is to install a case fan in the front of the case (which pulls air into the case) and a second case fan in the back of the case (which, with the power supply fan, helps exhaust hot air out the back). Standard sizes for case fans are 80 and 120 mm. Also, try to keep the computer in a relatively cool area and leave space for the computer to expel its hot air! Of course, there are other special considerations and options, such as liquid cooling and special processor cooling methods, such as oversized tower heat sinks; however, for typical workstations, these options will most likely not be feasible.
You should also train your nose for smells and watch for smoke. If a power supply starts to emit a burning smell, or if you see any smoke emanating from it, you should turn off the computer and disconnect the power right away. The power supply is probably about to fail, and it could short out, trip the circuit, or, worse yet, start a fire. Be sure to replace it. In some cases, a power supply has a burn-in period of 24 to 48 hours, during which time you might smell some oils burning off, but it’s best to be safe and check/test the power supply if you smell something that seems wrong.
