K. Less tired today. So looking at the
user manual again for the Asrock A75M-ITX mobo. On page 49, there are these options which include USB remote/keyboard/mouse to power on PC.
Restore on AC/Power Loss
This allows you to set the power state after an unexpected AC/power loss.
If [Power Off] is selected, the AC/power remains off when the power recovers. If [Power On] is selected, the AC/power resumes and the system
starts to boot up when the power recovers.
PS/2 Keyboard Power On
Use this item to enable or disable PS/2 keyboard to turn on the system
from the power-soft-off mode.
PCI Devices Power On
Use this item to enable or disable PCI devices to turn on the system from
the power-soft-off mode.
Ring-In Power On
Use this item to enable or disable Ring-In signals to turn on the system
from the power-soft-off mode.
RTC Alarm Power On
Use this item to enable or disable RTC (Real Time Clock) to power on the
system.
USB Keyboard/Remote Power On
Use this item to enable or disable USB Keyboard/Remote to power on the
system.
USB Mouse Power On
Use this item to enable or disable USB Mouse to power on the system.