How to turn off external usb hdd?

[fonon]

I'm using external usb hdd. The disk is still powered after system shut down. How to turn the hdd off?
f. ? /Mageia 3/

[doktor5000]

Use the power button of the HDD or unplug it? Or ask the disk manufacturer maybe ...

[fonon]

Use the power button of the HDD or unplug it? Or ask the disk manufacturer maybe ...

The disk has not the power button, of course. It is not a problem with the disk but with the operating system's power-off control. In MS Windows 7, when the OS is shut off, the power line in USB connector is probably turned off. In Mageia 3 the disk is still powered.
The general question is how to turn off or turn on the power line in the motherbord's USB connectors.
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[fonon]

Sometimes the external disk stops when the computer is switched off although I don't do anything special. Any idea?
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[jkerr82508]

Check the BIOS settings for "wake-up" options (probably in the Power Management section) and make sure that they are disabled. So long as you have any of those enabled, power may still be provided to the motherboard and/or other devices, even after the computer is "switched off", if it is still connected to the external power supply.

The best way to ensure that your system is fully powered off is to disconnect or switch off the external power supply (after "switching off" the computer).

IIUC, Windows overrides the BIOS power management settings, which may explain the different behaviour that you report.

Jim

[fonon]

Check the BIOS settings for "wake-up" options and make sure that they are all disabled. So long as you have any of those enabled, power may still be provided to the motherboard and/or other devices, even after it is "switched off", if it is still connected to the external power supply.

The best way to ensure that your system is fully powered off is to disconnect or switch off the external power supply (after "switching off" the computer).

Jim

It's a software problem. The BIOS "wake-up" option option is disabled. As I wrote, Windows 7 (installed on the same computer) turns off external disk properly - probably by the power control of the USB port (special software isn't installed). Now I see that Mageia 3 can do it too (I don't know how), but in most cases doesn't. I can "eject" external disk, but the disk is still powered. Is there a software tool for power control of USB ports?
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[fonon]

In suspend mode the external hdd is turned off properly. Why not in power off mode?
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