Asus V3-P5945GC - Manual (Page 56)

4-4 Chapter 4: Motherboard info
• The USB device wake-up feature requires a power supply that can
provide 500 mA on the +5VSB lead for each USB port; otherwise,
the system would not power up.
• The total current consumed must NOT exceed the power supply
capability (+5VSB) whether under normal condition or in sleep mode.
3. USB device wake-up (3-pin USBPW12, USBPW56)
Set these jumpers to +5V to wake up the computer from S1 sleep
mode (CPU stopped, DRAM refreshed, system running in low power
mode) using the connected USB devices. Set to +5VSB to wake up
from S3 and S4 sleep modes (no power to CPU, DRAM in slow refresh,
power supply in reduced power mode).
The USBPW12 jumper is for the rear USB ports (USB port 1-4). The
USBPW56 jumper is for the internal USB connectors (USB port 5-8)
that you can connect to additional USB ports.
R
USB Device Wake Up
3 2 2 1
PS2_USBPWR
(Default)
+5V +5VSB