A USB header is a set of pins on a computer motherboard that allows for connecting additional USB ports, typically for the front panel of a computer case. These headers act as dedicated connectors that send signals to Universal Serial Bus ports.
Understanding USB Headers
USB headers are usually located on the bottom or right edge of a motherboard. They should not be confused with other types of headers like audio, network, or parallel port headers.
There are four main types of USB headers corresponding to different USB generations:
- USB 2.0 header
- USB 3.0 header
- USB 3.1 Gen 2 header
- USB 3.2 Gen 2x2 header
To add more USB ports, you can:
- Duplicate a USB 2.0 header through manual wiring
- Use PCIe expansion cards for USB 3.0 and newer headers
Connecting devices to headers requires an internal USB cable. Proper connection is crucial to avoid errors like "USB Device Over Current Status Detected."
USB Header Types in Detail
- USB 2.0 header: Labeled "F_USB2", has 9 pins in a 5x2 grid
- USB 3.0 header: Labeled "USB 3.2 Gen1", has 19 pins in a 10x2 grid
- USB 3.1 Gen 2 header: Enclosed in a metal case with no visible pins
- USB 3.2 Gen 2x2 header: Similar to 3.1 Gen 2 but with dual channels
USB Header Splitter
A USB header splitter allows connecting multiple peripheral devices to a single header, increasing available USB slots. However, connected devices will share bandwidth, potentially affecting performance.
USB Header Pinout
Most motherboards use a 9-pin configuration for USB headers, arranged in two rows. Each header typically supports two USB connections. The pinout for a USB 2.0 header includes:
- VBus pins for power
- D- and D+ pins for data transfer
- Ground pins
- A key pin or drain pin
Wire colors often indicate pin functions:
- Red: +5V power
- White: USB-/Data-
- Green: USB+/Data+
- Black: Ground
Internal USB Header
An internal USB header is the connector on the motherboard that links to front panel USB ports via an extension cable inside the computer case.
Combining USB Headers
USB headers can be combined if they don't require additional power from 5V wires. This allows one header to support multiple ports. However, ensure proper wire connections and avoid overloading the USB bus.
Enabling USB Headers in BIOS
To enable USB headers in BIOS:
- Enter BIOS during system boot
- Navigate to USB Configuration settings
- Enable External USB Port
- Save settings and exit
Header vs Connector
- Headers are pin arrays on motherboards
- Connectors plug into headers
- Headers are a type of connector, but not all connectors are headers
- Headers are typically used in computer motherboards, while connectors have broader applications
Conclusion
USB headers play a crucial role in expanding a computer's USB connectivity. Understanding their types, functions, and proper usage can help maximize your system's capabilities and avoid connection issues.