i am using my Windows 10 thinkpad 10 (20C1)tablet for a carputer.
The problem I am having is that when I try to put the tablet to sleep, it keeps giving power to the usb hub ( the hub is self powered and does not need it)
Because the hub has 7 peripherals attached, the battery drain is not insignificant

I do not want to keep shutting down the tablet every time I leave the car, and unfortunately, hibernation is flaky for the programs I am using.
So......... I have tried ''disable/suspend usb device/s when asleep'' - this is always checked, but no joy.
''disabling device to save power'' for usb root hub via device manager- this is also checked - no joy
I have tried most things ( including a registry change), but the tablet still provides power to the hub in sleep.
The thinkpad BIOS is very basic, and does not include any usb power management.
Also, this is NOT an ''always on'' usb port.
The tablet is up to date according to the Vantage app, and the windows version is 1909
So I am stumped! - am I missing something??
Many Thanks
Pootler