Build Your Own

Home PC Computer System

For me, one of the major attractions of building my own home PC computer system is to save money. To that end, I don't want to see the PC system I carefully thought out, invested time to find the right parts at the right price, and built myself go up in an acrid plume of blue smoke. Unless you're like Richard Pryor in Brewster's Millions and have to find a way to throw away your money I suggest you take special consideration to maximize your CPU cooling.

CPU Cooling

CPU cooling is very important and should not be overlooked. A less than average CPU temperature prolongs CPU life (up to more than 10 years). On the other hand high CPU temperatures can cause unreliable operation, such as computer freezes, or slow operation. Extremely high temperatures can cause immediate CPU destruction by melting the materials in the chip and changing the physical shape of the sensitive transistors on the CPU. Because of this, never switch on the computer if your CPU has no cooling at all. It is an extremely stupid thing to do, the scenario of "I'll just test whether my CPU works!" as by doing so, you would find that the CPU fries in less than 5 seconds and you will be off to buy a new one.

Most CPU installations use forced-air cooling, but convection cooling and water cooling are also options. For traditional forced-air cooling, the heat sink and fan (HSF) included in most retail CPUs is usually sufficient to cool the CPU at stock speed. Overclockers might want to use a more powerful aftermarket fan, or even try water cooling because they need additional cooling ability given the increased heat of overclocking.

HSFs with decent performance are usually copper-based. The cooling effect is enhanced if the HSF has heatpipes. Silent (i.e. fanless) HSFs are there to provide users a nearly silent cooling.

Many retail heatsink+fan units have a thermal pad installed, which transfers heat from the CPU to the fan helping diffuse the heat created by the CPU. This pad is usable only once. If you wish to remove the fan from another CPU so that you can use it on your new one, or need to take it off for some reason, you will need to remove it, and apply a thermal paste or another thermal pad. Note that some of the cheaper pads can melt in unexpected heat and may cause problems and potentially even damage if you are overclocking. In either case, thermal paste is usually more effective, just harder to apply. If you plan to do any high performance computing, or removing and replacing the HSF, often thermal paste is suggested. If you are planning a long term installation a thermal pad is suggested. Non-conductive thermal pastes made up of silicon are the cheapest and safest.

Silver-based thermal pastes sometimes perform better than normal thermal pastes, and carbon-based ones perform better still. When applied improperly both can be conductive, causing electrical shorts upon contact with the motherboard. A thin properly-applied layer will usually prevent this problem, though some pastes can become runny when they get hot. Users should also beware that many "silver" thermal pastes do not actually contain any silver metal.

For quiet operation, start with a low-heat (low number of watts) CPU. Processors made by VIA, such as the VIA C3, tend to produce low amounts of heat. The Pentium M gives performance that is on par with many of the desktop processors, but gives off more heat than the Via processors. You can also underclock your CPU, giving up some unneeded performance for some peace and quiet. Another option is to choose a large copper heat sink with an open fin pattern. However, true fanless operation is difficult to achieve in most case designs. You can position a case fan to blow across the heat sink, or mount a fan on the heat sink. With either choice of fan placement, choose a large and slow fan over a small and fast fan to decrease noise and increase air flow.

Some low-noise CPU cooling fans require special mounting hardware on the motherboard. Be sure that the cooling fan you choose is compatible with your motherboard.

Zalman CNPS7000B-AlCu LED Aluminum/Copper CPU Cooler with Blue LED (Socket 478, 462, 754, 939, 940)