What I found thus far... mostly marketing hype
*With a simple On/Off Charge driver update, GIGABYTE motherboard users are able to take full advantage of USB charging of their iPhone/iPad/iPod Touch, giving them more options and convenience when recharging their new device.
* Due to certain mobile phone limitations, users may need to connect the mobile phone to their PC before the PC
enters S4/S5 mode to enable a quick charge from non ON/OFF Charge USB ports.
* Maximum 3 devices can be charged at the same time. Charging current may vary with PSU 5V stand-by spec.
On/Off Charge driver download
When you install the ON/OFF charge driver, please update the latest BIOS version for the best product efficiency.
What device are you charging? Release notes I found state - (Note) Support iPhone/iPad/iPod touch devices with iOS 6.x, 7.x, 8.x.
I don't use the feature, so am not sure what the requirements are or how many mA you get, but it may depend on your PSU. I'll keep looking.