🚀 go-pugleaf

An ATX power supply (the kind used by almost all recent systems) is ALWAYS
partially ON (the 5 VDC Standby output that can supply about 1 ampere)
unless it is unplugged from AC power or the AC switch (if any) on the back
of the power supply is turned off.  The power button on the front of the
system case is just a momentary contact switch that uses circuitry on the
motherboard to switch the system ON or OFF.  When the system is switched
OFF, the power supply is operating, but it supplies power only to the 5 VDC
standby connector.  This 5 VDC standby power is used to run the power
control circuitry on the motherboard and is also used to run WAKE-ON-LAN
network devices and to allow turning the system on by using a key on the
keyboard or by using the mouse.  Once the power control circuitry asks for
power on the other output lines from the power supply, it checks that the
voltages are ok before allowing the system to boot.  If the other voltages
are not correct the control circuitry shuts down the power supply.

This is a change from the AT power supply specification and is a good step
forward:

Advantages:

No line level AC voltage is anywhere in the system case except for INSIDE
the power supply box

Ability to power up the system remotely

Ability to set the system to power up when addressed by a network

Automatic shutdown if the voltages are not correct.



--
Phil Weldon, pweldon@mindspring.com

Always look for ACHO seal of approval:
ACHO Group Overclocking FAQ -
http://www.hyperformance-pc.com/overclocking_faq.htm

"Sunny" <wombathouse@yahoo.com.au> wrote in message
news:H0C%9.10697$DC6.39348@news-server.bigpond.net.au...
Just bought 2 x Optical mice and noticed that power is still supplied to the
ps/2 mouse
when the PC is shut down.
An Aptiva (with the same mouse) does not power up the mouse, when it is shut
down.
BIOS is set to "button only", and that is the only settings I can find that
mention mouse
and power in the one sentence.
Only noticed it because the mouse lights are on all the time on the Abit
board but off
on the IBM Aptiva board.
Anyone know if the BX6 Rev2 is supposed to power up the ps/2 port even when
PC is off?