Need 'always on' +5V from motherboard

[bwpotter]

I've got a older ECS P4S5A/DX+ motherboard connected to a 'Touch-Sensitive Series' ATX case. I recently got the case surplus with no manual. I'm having issue trying to turn on the computer using the touch-sensitive front switches, which require +5V to the switch array. I'm wondering if there is a standard set of pins or a power connection were +5V may be available when the computer is off?

I can turn the computer on by cycling the P/S switch and then touching the 'on' switch. I can also turn it off with the motherboard and power supply cycling down. However, to turn it back on, the touch pad requires a power feed. Currently, I've supplied +5V via a Molex connector.

Any ideas or suggestions?

Thanks... Brian

 

[Mark R]

A permanently on +5V line (5V standby) is only provided on the large 20/24 pin molex connector (the purple wire). The other connectors including the hard drive connectors are only supplied with power when the system is operating.

You'll somehow need to tap into the 5V standby line and run that to the case switches.

 

[Fullmetal Chocobo]

Originally posted by: Mark R
A permanently on +5V line (5V standby) is only provided on the large 20/24 pin molex connector (the purple wire). The other connectors including the hard drive connectors are only supplied with power when the system is operating.

You'll somehow need to tap into the 5V standby line and run that to the case switches.

Maybe solder a line to the back of the solder joint on the back of the mobo? That should work, I would think...

 

[bwpotter]

OK... I think I'll splice into the purple wire feeding from the power supply.

Thanks guys... Brian

 

[futuristicmonkey]

Look at the manual for your power supply to find the 5VSB line. You'll also need to see how much current can be sustained by it, since I believe it is regulated by a small, linear IC that is probably only capable of sustaining 1 ampere of continuous current.