Power Supply
Most system cases come with a power supply (see Figure 15-20) matched to its form factor.
However,thepowersupplyisnotapartofthecase,eventhoughtheyaregenerallysoldto-
gether as one assembly. When buying a PC case, be sure that a power supply that is appro-
priate for your application is included or, if you prefer, that a power supply is not included.
Many case manufacturers allow you to customize their cases to meet your needs.
See Chapter 14 for more information on power supplies.Auxiliary Fans
The main cooling fan in the PC is in the power supply. This is one of the very important
reasons that you should match the power supply to the form factor of the motherboard
and case, in that order. Many newer case form factors provide a location for an auxiliary
or supplemental fan to help cool the inside of the PC. Typically, the location of the auxil-
iaryfan,ifavailable,willbeontheoppositefrontorbackpanelfromthemaincoolingfan,
as shown in Figure 15-21.Chapter 15: The System Case^363
Figure 15-20. A power supply may be purchased separate from the system case. Photo courtesy
of AOpen America, Inc.