I had to disconnect the ac cord from the unit. yet it still lights up and my web cam is working. Is the ac needed?
Thank you for contacting us about your hub. The AC is definitely needed.
If the AC power is disconnected from the hub, it will switch over to using power supplied by the computer. However, that power is very limited: only 500mA (it also drains the computer’s battery if it is a laptop). It is usually enough to power one connected device, but if you plug in more, eventually you’ll need too much power, and either the computer will disconnect the devices until it is back to 500mA or your devices will not work correctly.
The AC adapter for your computer supplies 2500mA, or five times more than it can get from the computer.
I hope this answers your question.