The Motherboard, Processor, and Memory - Cooling
(Page 7 of 18 )
As processors have become more sophisticated, they’ve grown in the sheer number of transistors they incorporate. More transistors means more current is passing through them, and more heat is generated. Today’s processors require active coolers (heat sinks with fans attached). Earlier processors used passive coolers (heat sinks without fans), and even earlier ones didn’t require cooling at all.
If you run a current processor without a cooler, it’ll fry itself permanently in a matter of seconds. With the number of transistors in processors skyrocketing, cooling is becoming more and more important to processor health.
One thing in our favor that helps keep processors from melting down is the continually shrinking die processes used by chip makers. The process indicates the spacing and the size of the components on a chip. To give you an example of how quickly chips are shrinking, consider that in 1990 most processors were made on a 1-micron die. Current Pentium 4s are made on a 0.13-micron die! The smaller the process a processor is built on, the less heat it generates.
So the heat battle is balanced: as the die shrinks, the more transistors are crammed into a chip. More transistors make a hotter chip; smaller processes run cooler.
No matter what, you’ll need an active heat sink on your processor. If you buy it in a retail kit, rather than a “white box,” you might get an appropriate cooler right in the package. However, if you go the cheaper route of getting an original equipment manufacturer (OEM) processor, you’ll need to buy your own cooler.
Currently, Athlons and Pentium 4s require different coolers. Athlon coolers fasten to little hooks right on the socket, while Pentium 4 coolers fasten to the motherboard via a housing that surrounds the socket.
Your cooler will consist of a large heat sink—a metal block, usually aluminum or copper or a mix thereof, with fins or pillars designed to dissipate heat from whatever it’s attached to. It will include a fan attached to the heat sink, to help speed the heat dissipation. It’ll also come with mounting hardware. Most coolers come with a strip of thermal tape or a small amount of thermal paste, which is necessary to ensure good contact between the cooler and the CPU, as each may have imperfections on its surfaces that, on a microscopic level, keeps it from being perfectly flat. Figure 2-2 shows an example of a CPU cooler.
Coolers can be purchased at most computer stores and at cooling-dedicated sites such as www.frozencpu.com and www.coolerguys.com. Brands such as Thermaltake and Alpha make excellent active coolers, and some of their wares come with nifty-colored LEDs. Make sure you get a cooler rated for the clock frequency of your CPU.
Figure 2-2
A Thermaltake Volcano 7 CPU cooler
You may also need thermal paste if it doesn’t come with the unit. Some coolers come with thermal tape fixed to the area of the heat sink that will make contact with the processor. If yours doesn’t, you’ll need thermal compound (shown in Figure 2-3), such as Arctic Silver III, which is available at the web sites just mentioned. Thermal compound or tape is necessary to foster good contact between the heat sink and the CPU, which in turn ensures that the cooler will whisk heat away from the CPU.
Coolers Are Not Optional: Without proper cooling, your CPU won’t operate properly. It might even roast itself to death. A good cooler is not an option; it’s a necessity. Never operate a PC without an active cooler affixed to the CPU, even for a few seconds. That’s all the time it takes for a CPU to destroy itself.
Figure 2-3
A tube of thermal compound
For the hardcore, there are alternatives to simple air/heat sink cooling. You can purchase water cooling kits, which run water from a reservoir through a radiator and then through a block attached to a processor. Some people even use Peltier elements, which are flat, electronic elements that aggressively pull heat from one side and dissipate it through the other. Such coolers are used mainly for overclocking the processor.
 This chapter is from Build Your Own High Performance Gamers' Mod PC, by Chen and Durham (McGraw-Hill/Osborne, 2004, ISBN: 0072229012). Check it out at your favorite bookstore today. Buy this book now. |
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