What Gauge Wires Are Used in Computers?

By Tom Lutzenberger

Cables inside a computer connect various pieces of internal hardware to the power supply.
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Computer internal hardware operates and communicates with all sorts of electrical wiring. From power cables to data feed lines, wires proliferate inside the machine between all of the hardware. Most of the internal hardware comes pre-wired so it just needs to be plugged in when installed. However, you may find yourself wanting to patch a frayed wire instead of replacing a whole unit. In this case, knowing the wiring gauge can be very helpful.

Basic Power Supply Wiring

Peripheral power supply wiring for hard drives, floppy drives, and CD or DVD drives tend to use 18 gauge wire. The power wiring may involve up to six different wires of multiple colors, but the sizing the same. All of the wiring feeds out of the computer power supply unit and travels to junction plugs. The plugs are then inserted into the given peripheral to feed electricity to it.

Data Feed Cables

Data feed cables in standard computers utilize what is known as IDE/ATA cables. These ribbon-like cables are made up of 40 different small wires connected together with the same insulation material. Each of the wires tends to be fairly small and thin since they measures 30 gauge. The data doesn't need large copper wire to travel, but with so much data to move, 40 small wires are needed.

Network Junctions

The common wiring size for network junctions inside and outside a computer tends to be Cat 5 wire. In some cases Cat 5e and Cat 6 wiring is used instead. This type of wire is uniquely suited for data transmission of a much larger size over long distances, unlike the short, simple jumps necessary inside a computer box.

USB Wiring

Universal Serial Bus, also known as USB, wiring has been expanding as a commonly used external computer wiring between peripherals. This type of wire actually incorporates four or more wires inside. Two of the wires are for power transfer and tend to be either 28 or 20 gauge wiring. Two more wires twisted together tend to be 28 gauge and provide the actual data conduit. Finally a sink line is wrapped into the mix as well which also measures 28 gauge.