THE POWER SUPPLY

The "power supply," as its name implies, provides the necessary electrical power
to make the PC
operate. The power supply takes standard (in the U.S.) 110
-
volt AC power and converts it into 12
-
volt, 5
-
volt, and 3.3
-
volt DC power. The vast majority of power supplies are about the size of a
shoebox cut in half, and are usually gray or me
tallic colored

A number of connectors lead out of the power supply. Every power supply pr
ovides special
connectors for the motherboard (Figure 1
-
22), and a number of other "general
-
use" connectors
that provide power to any device that needs electricity

ou can see the p
ower supply if you look at the back of your PC. It has a connection for a power
plug that in turn runs to an electrical outlet and also has a big fan inside. Every PC uses a fan or
two to keep the interior of the PC cool (Figure 1
-
24). Check out both the P
ower Supply and
Motherboard chapters for information detailing power supplies.