Question About Computer ATX PSU
Posted: Sun May 26, 2019 9:05 pm
In this article (and many others) there is a wire color chart for ATX power supplies:
https://www.instructables.com/id/A-Make ... -Supplies/
I want to add a switch that will temporarily disable the automatic power-off
feature provided on most mobos (motherboards). Just to be clear, the operating
system shuts down and almost immediately after the PSU powers down. That's
the auto power-off feature.
I've built many desktops, but I never had a reason to change how the PSU operates.
I don't want to make a mistake and damage the mobo or PSU.
Here is a quote from the wire color chart:
"Connecting this wire to the black (ground) wire will pull the green wire's +5v signal
low, signaling the PSU to turn on. If you want an on/off switch, it should be this
connection."
I assume there is a control pin on the mobo that is normally low. This would keep
the green wire at ground and the PSU powered up. After operating system shutdown
the control pin flips high, powering down the PSU.
The question is, how to implement manual control of auto power-off. Something
very simple like adding an inline SPST switch to the green wire? I can't afford to
guess with a very expensive desktop. How should it be done?
(After googling about this topic I found some really uninformed suggestions, like
disabling Power Management ACPI in the BIOS. Not a good idea!)
https://www.instructables.com/id/A-Make ... -Supplies/
I want to add a switch that will temporarily disable the automatic power-off
feature provided on most mobos (motherboards). Just to be clear, the operating
system shuts down and almost immediately after the PSU powers down. That's
the auto power-off feature.
I've built many desktops, but I never had a reason to change how the PSU operates.
I don't want to make a mistake and damage the mobo or PSU.
Here is a quote from the wire color chart:
"Connecting this wire to the black (ground) wire will pull the green wire's +5v signal
low, signaling the PSU to turn on. If you want an on/off switch, it should be this
connection."
I assume there is a control pin on the mobo that is normally low. This would keep
the green wire at ground and the PSU powered up. After operating system shutdown
the control pin flips high, powering down the PSU.
The question is, how to implement manual control of auto power-off. Something
very simple like adding an inline SPST switch to the green wire? I can't afford to
guess with a very expensive desktop. How should it be done?
(After googling about this topic I found some really uninformed suggestions, like
disabling Power Management ACPI in the BIOS. Not a good idea!)