Hardware Reference
In-Depth Information
Figure 18.18. Power supply remote pushbutton switch connections.
Caution
Although these wire color-codings and parallel/angled tabs are used on most power supplies,
they are not necessarily 100% universal. I have encountered power supplies that do not use the
same coloring or tab placement scheme described here. One thing is sure: Two of the wires
will be hot with potentially fatal AC voltage anytime the power supply is plugged in. No matter
what, always disconnect the power supply from the wall socket before handling any of these
wires. Be sure to insulate the connections with electrical tape or heat-shrink tubing so you
won't be able to touch the wires when working inside the case in the future.
As long as the blue and brown wires are on one set of tabs and the black-and-white leads are on the
other, the switch and supply will work properly. If you incorrectly mix the leads, you will likely
blow the circuit breaker for the wall socket because mixing them can create a direct short circuit.
Motherboard Power Connectors
Every PC power supply has connectors that attach to the motherboard, providing power to the
motherboard, processor, memory, chipset, integrated components (such as video, LAN, universal
serial bus [USB], and FireWire), and any cards plugged into bus slots. These connectors are
important; not only are these the main conduit through which power flows to your system, but
attaching these connectors improperly can have a devastating effect on your PC, including burning up
both your power supply and motherboard. Just as with the mechanical shape of the power supply,
these connectors are usually designed to conform to one of several industry-standard specifications,
which dictate the types of connectors used as well as the pinouts of the individual wires and
terminals. Unfortunately, just as with the mechanical form factors, some PC manufacturers use power
supplies with custom connectors or, worse yet, use standard connector types but with modified
(incompatible) pinouts (meaning the signals and voltages are rearranged from standard
