modern ATX/P4 case power button...

[araczynski]

Hello,

i'm considering doing my own case/mod (converting an old Gateway 486dx2/66e tower for new system), but am wondering about the power button on the front. Those of you old enough might remember that the power supplies were connected directly to the front power buttons back in the days. Obviously i'll have to replace the button mechanism with something else, but was wondering what are the electrical requirements of the modern switches are so that when i hook it up to the motherboard it doesn't go *poof* on me

if you know of any site/info i would appreciate it greatly.

TIA
andy

 

[araczynski]

anyone?

 

[MDE]

You could try dissecting an old ATX case and use that power button. In all actuality, all you have to do is cross the wires that go to the motherboard power switch header.

 

[Budman]

You can use an old reset switch that the AT cases used to power the new ATX mobo.

 

[MDE]

Originally posted by: Budman
You can use an old reset switch that the AT cases used to power the new ATX mobo.

Or just use the reset switch on the case right now and just cut off the switch from the old PSU or put one on there so the old power button looks right.

 

[VansTheMan]

I'm about to be doing the same thing to an old case that I'm going to build my system in. The power switches now are just momentary switches that you should be able to get at Radio Shack or any electronic components store. You should be able to use any momentary switch that's rated at 5v/3A or more. I think the power button only uses the 5v stand-by rail, but I guess it could also be on the regular 5v rail. I think most power supplies have about a 2.2A rating on the 5v stand-by rail.

 

[MDE]

Actually, I think they use the 3.3V rail. When people ask about how to start an ATX PSU without a motherboard, they're told to cross a green wire on the mobo connector with a ground, and I'm pretty sure the green wire is 3.3V.

 

[araczynski]

Thank you guys, perfect answers, several very good choices.

Appreciate it.
andy