NWA-PCUG Newsletter Article, October 2004
Keep Your Cool – Your PC Cool That Is
by Ira Wilsker, APCUG BOD

Heat is one of the primary causes of premature computer and component failure. Today’s microprocessors, video cards, hard drives, CD and DVD burners, memory, and other components produce much more heat than their earlier brethren. One simple indication of the amount of heat generated in today’s newer computers is the power supply; older computers could run well with a 150 watt power supply, while many newer models utilize a 400 watt or larger power supply. While it is uncommon for computers to use all of the power capacity of the power supply, the immutable laws of physics state that much of the power used will be turned into heat, and heat can kill computer components.

Many newer motherboards and computers now come with some form of thermal monitor to inform the user of potentially damaging or dangerous overheating, and a device may even shutdown a computer unexpectedly if temperatures inside the computer get too high. If there is too much heat buildup, and the internal temperatures get too high, parts degrade or fail at a rapid rate. Expensive CPU chips, hard drives, memory, and video cards that fail are often the result of overheating. Sudden lockups and computer errors may be due to an overheated CPU chip. Our critical data may be lost forever if our hard drives overheat and fail. If our computers can be protected from overheating, not just will they last longer, but they may perform better.

Intel provides a free temperature monitoring utility for its motherboards and chipsets that support this feature. According to Intel, desktop Pentium IV chips work best when below 130 degrees F, may have problems at 150 degrees F, and may start to degrade or fail at that temperature or higher. AMD chips, such as the Athlon may suffer a similar fate from overheating. For this reason almost all modern CPU chips have an attached heat sink and fan. In order to improve thermal conductivity between the surface of the chip and the heat sink, a thermal grease substance is used between them. The purpose of a heat sink is to provide a greater surface area to enable the dissipation of heat into the surrounding air. Most CPU chip heat sinks are topped with a small fan to blow air through and around the heat sink to better cool the chip. While simple in concept, and inexpensive to produce, this is also a common cause of overheating that is easy to rectify. The same dust and debris that can clog our household furnace filters can accumulate and clog the passages in the heat sink, and obstruct the blades of the chip fan. It is good practice to periodically unplug the computer, practice safe electrical safety, and remove the “dust bunnies” from the fan and heat sink with a small vacuum, canned air, or a cotton swab. You may also want to read the label on the chip fan to see if it is a “sleeve” or “ball” bearing. Sleeve bearings tend to have a shorter life before they fail, and can lead to premature chip failure due to overheating. Ball bearing fans are slightly more expensive, but tend to last much longer, providing for more reliable chip cooling.

The power supply also has a fan, which for many computers, is the primary cooling component that exhausts the hot air from inside the computer. If this fan fails, or becomes obstructed with dust and other debris, the computer will overheat. This fan must also be frequently inspected, and cleaned as necessary with a small vacuum, or canned air. If the fan starts to squeal, or otherwise appears to fail, it is imperative that either the fan or the entire power supply be promptly replaced.

Many computer cases have a space and mounting for an additional fan; if available, the additional fan should be installed. They are readily available, and inexpensive.

Supplemental cooling is also available, and can be easily self installed. One of the simplest to install is an exhaust fan that sits in a vacant PCI slot, which almost all desktop computers have. These fans which typically exhaust air from the computer can either be powered by the PCI slot, or by a power cord connected to a plug inside the case. These are especially effective at cooling video cards which generate a lot of heat; Intel recommends that the video cards be kept below 105 degrees F. Again, the slightly more expensive ball bearing fans are considered superior to the less expensive sleeve bearing fans. I installed one of these in my computer, and internal temperatures are consistently about 20 degrees F cooler than before.

Other formats of supplemental cooling are available, such as fans that can be mounted in the front of the computer in a vacant drive bay, also common on most computers. These can be simple propeller fans, or powerful turbine fans, and can either push cool outside air into the box, or exhaust hot air from the box. Other fans can be mounted on a hard or CD/DVD drive to cool those hot running devices. Some powerful computers, such as the popular gaming machines may now utilize a water cooled device, similar to an automobile radiator, complete with antifreeze. Notebook computers, which are often especially subject to overheating may be cooled by mounting them such that air can circulate all around the case (some people sit their notebooks on a cake rack), or on a notebook cooling pad that contains its own fans. One pundit has been recommending those black painted aluminum sheets from a dollar store that are advertised to quick defrost frozen foods, as they are an excellent heat sink.

Whatever you do, keep your cool – your computer cool, that is.

There is no restriction against any non-profit group using this article as long as it is kept in context with proper credit given the author. The Editorial Committee of the Association of Personal Computer User Groups (APCUG), an international organization of which this group is a member, brings this article to you.

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