How to disable the 5 V output at USB ports

Chan

How to disable the 5V output at the USB port of Aspire TC 605 when the desktop is turned off.

philetus

Turn off the switch on the power supply

Chan

By unplug or switch off is one of the methods, can it be disabled by setting the software?

philetus

You can try in your power Options/Change advanced options/usb settings/USB selective suspend settings to disabled. I doubt if it will do what you want.

It's built into the MB so you can charge your phone etc. when the computer is off.

I think your only option is to turn off the power. 

Chan

The Power Option does not allow me to do what I want.

 

My Samsung Ultrabook 9 has a setting to do this.

 

philetus

Was it because the setting wasn't available?

Did you click this?

Chan

My Power Option display is sames as yours, even I clicked what you circled, there is no option related to the 5V power supply at USB port, the only option related to USB deals with USB Selective suspend setting, which does not relate to the 5V power.

 

The Power Option display is same in Vista, Windows 7, windows 8.1 and Windows 10. 

 

Before Windows 8 there is no 5V power supply at the USB port.

JordanB

I don't see anything in the UEFI settings to disable it.  Obviously you could pull the power cable or if your Power Supply has a switch, you could turn it off at the switch.  My power supply doesn't have a switch, but of course if I replaced it.....it would have a switch.  I guess you could flip off the power at your surge protector switch too.....which might be the easiest and cheapest workaround.

 

Since they intentionally designed it to provide USB power when the computer is shutdown, I don't think they included a way to disable it in the BIOS/UEFI.

 

If you figure out a way to disable it, please post.  For the longest time, I couldn't figure out why I was getting power out of that USB port when the computer is shutdown.....I think I need glasses.  

 

I'm actually using that USB port to charge my tablet at night, so I'm not overly eager to disable it personally.....

 

Chan

There are discussions on this topic on the internet, it seems switch off power to the desktop is the only solution.

 

The maxinum output at the USB 3 port is 0.8A, It may take more time to charge smart phones such as Samsung S4 with the USB port than using its original charger.