The +5 Volt standby is the signal that turns on the PC when you press the power on switch. This voltage is normally present when the computer is "off" and is seperate from the normal 5VDC line. The toggle switch on the back of the ATX power supply shuts this power off. Many motherboards have an LED that illuminates when this voltage is on. This voltage is also used for wake on xxx functions.
AFAIK you will need still need to provide this voltage even though your not going to use any standby functions.
Last edited by michaelk; 05-02-2006 at 05:02 PM.