I have a Kensington dock (with video) for my Dell Inspiron 9300 laptop. I have a monitor, keyboard, mouse and external sound system connected to the dock. I also have USB hubs connected for various devices: printer, two external hard drives, webcam, camera, phone, iPod. It means I can move the laptop by disconnecting the power and one USB cable. Is there a limit to what can be connected though one port? Tom Corcoran
A USB host can support up to 127 devices in a "tiered star" formation, but you can run out of bandwidth if you use too many of them at once. Running a video while writing to both drives could be a challenge, for example. You can also run out of power: a USB device can request up to 500mA, but a non-powered hub can only supply 400mA to be shared between four devices. Using powered hubs usually avoids problems. USB devices don't speak unless spoken to, so it shouldn't matter how many you have connected but idle, as long as each one has its own 7-bit address.
