Cooling

Small desktop PCs need some attention to cooling. They need fans because they are built around desktop components and to accommodate at least some low-profile expansion cards. On the other hand, they do not require the several large fans of a high-performance, high-power PC. The lower the power consumption of the CPU and the whole system, the less cooling it needs.

The 80-92mm fans in SFX and TFX power supplies help cool the entire case. In addition, a fan may be needed in front of the expansion slots if a graphics card is installed, or even just for better cooling of the northbridge and other components.

Even a mid-power CPU (up to about 65W) needs special consideration in a small case. Low-profile designs with an optical drive above the CPU (about the only place where one will fit in a case less than 10 inches deep) have less than the 3 inches (76mm) of clearance above the motherboard that microATX requires and thus do not fit stock coolers.

One possibility is to remove the fan from the stock heat sink and mount it nearby, or to mount a smaller 40-50mm fan near or directly behind the heat sink. Another is to use a very low-profile heat sink and mount a fan on top of it, with air guides to ensure that the fan draws cool air.