Vista - in hibernation-- turning off usb device connected via USB hub--

Vista Home Premium, Desktop, several USB ports.
Issue related to Hibernation, not sleep.


Have a 7 port USB hub, to which a device (external HDD) is connected.
The device is a 120Gb external non a/c powered HDD.

I wish to have device turned 'off' when the computer hibernates (that is no
green light on device, no lights at all on the computer either).

If device is connected directly to the computer turns off device in
hibernation (no lights at all),
if the device is connected to the computer via the 7 port USB hub, device -
HDD--
stays 'on' (green light stays on).

Please advise the detailed instructions to make the external HDD device turn
off (no light) when connected to the computer via the hub and computer goes
into hibernation.

Thanks in advance,
Robert