Power Supplies - Upgrading and Repairing PCs - page 1116

theseconnectorsarekeyedandthereforedifficulttoinsertincorrectly. Figure18.29 shows
the keying with respect to pin numbers on the larger drive power connector.
Figure 18.29 A peripheral power connector.
This is the one connector type that has been on all PC power supplies from the original
IBM PC to the latest systems built today. It is most commonly known as a disk drive con-
nector ,butitisalsousedinsomesystemstoprovideadditionalpowertothemotherboard,
video card, cooling fans, or just about anything that can use +5V or +12V power.
A peripheral power connector is a 4-pin connector with round terminals spaced 0.200
inches apart, rated to carry up to 11 amps per pin. Because there is one +12V pin and one
+5V pin (the other two are grounds), the maximum power-handling capability of the peri-
pheral connector is 187 watts. The plug is 0.830 inches wide, making it suitable for larger
drives and devices.
Table 18.19 shows the peripheral power connector pinout and wire colors.
Table 18.19 Peripheral Power Connector Pinout (Large Drive Power Connector)
Floppy Power Connectors
When 3 1/2-inch floppy drives were first being integrated into PCs in the mid-1980s, it
was clear that a smaller power connector was necessary. The answer came in what is now
known as the floppy power connector , which was created by AMP as part of the eco-
nomy interconnection (EI) series. These connectors are now used on all types of smaller