This page provides the basic instructions you will need to install your USB cable.

If you would like a more detailed explaination of how the USB pin headers on motherboards and devices are used please use the link below :-

Goto a simple guide to USB pin headers

Internal USB cables

When you fit an internal USB cable you need to check that the wires in the cable are connected to the correct pins on the USB pin header. This is important because there is no standard layout for the wires on an internal USB cable connector. Connecting the cable incorrectly can damage your equipment.

Checking or assembling your cable is easy because the wires are colour coded. No special knowledge is required. All you need to do is make sure that each coloured wire is matched to the correct pin on the USB header as shown below. The connectors used on internal cables are designed so that it is easy for you to assemble or modify the cable to suit your equipment.

Information you will need

Most manufacturers use the same style of USB pin header but they do not always use the same layout for the pins. This means that you need to check your motherboard and/or device doumentation to find out the particular pin layout used by your equipment.

The manufacturer will normally include a diagram in their manual or on their website showing you which wire should be connected to each pin on the USB header. You may also find that the pins are labelled on the circuit board. The table below shows the symbols used for each wire.

Symbol Wire
V, VCC, or +5V RED
D- or Data- White
D+ or Data+ GREEN
G,GND or Ground BLACK

The pictures below show some of the common layouts for USB pin headers on motherboards and devices. Note these are only shown as examples. You need to consult your own equipment documentation to find out the specific layout used on your motherboard and devices.

Sample USB Pin Header Layouts

Sample USB Pin Header Layouts

Note -

Motherboard USB headers will almost always have two rows of 4/5 pins. USB devices may have one or two rows of pins.

The pin labelled s-gnd on some pin headers is an optional connector. You do not need to connect a wire to this pin. Some pin headers have more than one pin labelled gnd in each row of pins. These extra gnd pins are also optional.

Assembling and checking your cable

To assemble or check the configuration of your cable you will need to consult your motherboard and device documentation. You should find a diagram similar to one of the above.
You should make sure that the pins are inserted into the connectors so that :-

  • The red wires are connected to the pin labelled V, VCC or +5V.
  • The white wires are connected to the pin labelled D- or Data-.
  • The green wires are connected to the pin labelled D+ or Data+.
  • The black wires are connected to the pin labelled G,GND or GROUND.

    If your cable came pre-assembled and the supplied configuration does not match the diagram for your equipment, remove the relevant pins and re-insert them in the correct postion. (see the pictures below for an illustration of removing and inserting pins).

    Once the cable has been assembled and checked you can plug the connectors onto the pin headers on your motherboard and device.

    When connecting the cables you just need to ensure that the plugs are in the correct orientation. To do this make sure that the red wires are connected to the V,VCC or +5V pins.

    Inserting and removing pins from the connectors

    The pins in the connectors used in the USB cable are designed so that they can be easily assembled and modified.
    The pins simply push into the square holes at one end of the connector as shown in the picture below. The small plastic tabs on the plug hold the pin in position once it is inserted.

    Adjuting pin position in header

    If you need to change the order of the wires in the connector the pins can easily be removed. Using a needle or some other small sharp object gently raise the plastic tab that holds the pin in position. Then gently pull on the wire to remove the pin. The tab should only be raised by the small amount needed to remove the pin. If the tab is pushed to far back it may not return to the correct postion to hold the pin in place.

    Adjusting pin position

    Top of page