If you are experiencing any power issues with the 6 USB when connected directly to a Windows PC you should follow the steps below:
1. Click Start, Open Control Panel and click on Device Manager.
2. Expand the Universal Serial Bus Controllers menu.
3. Right click on each of the USB Root Hub in the menu and choose Properties
4. Select the Power Management tab and uncheck the box "allow the computer to turn off this device to save power".
If this doesn't solve your power issues, try using a different cable or connecting the 6 USB via a powered hub.