How to Examine USB Hubs

Connecting a USB device to a computer can include several different layers:

• A USB host controller, which is connected directly to your computer USB host controllers are often built into the computer's motherboard, but you can add them by using an internal adapter or a PC card. If the name of the controller includes the word "Enhanced," the controller supports USB 2.0.
• A USB root hub, which is connected directly to the USB host controller Typically, USB root hubs are built into the same device that contains the USB host controller- your computer's motherboard or an adapter card.
• Optionally, additional USB hubs that connect to the USB root hub to create additional USB ports USB hubs can be external devices that you add, they can be an internal device within a computer, or they can be built into a docking station.

You can use Device Manager to examine the USB controllers and hubs in a computer, determine their power capabilities, and examine the power requirements of the connected devices. This can help you to identify the source of a USB problem. To examine USB devices, follow these steps:

1. Click Start, right-click Computer, and then select Manage.
2. In the Computer Management console, click Device Manager (under System Tools).
3. In the right pane, expand Universal Serial Bus Controllers.
4. Right-click an instance of USB Root Hub (there might be several) and then click Properties.
5. Click the Power tab. This tab displays the power capabilities of the hub and the power requirements of every connected device. To determine the requirements of any specific device, disconnect the devices and connect them again one by one.