Dell Optiplex 780 - Wiring power switch help

[tylerwerrin]

Hi guys,

I got a Dell Optiplex 780 from work that I want to use as my Mame station - I was wondering if anyone can help me figure out how to wire an external power switch that will turn it on. On the Optiplex 740 that I had previously, i just spliced in a wire into the existing power switch - however on the 780, the switch is a very tiny momentary microswitch which is soldered to a small board.

I'm guessing that I will need to splice directly into the powersupply itself - but I am not sure which wires control the switched power. Can you help me out?

Thanks!

[processedmeat]

Try this:

[tylerwerrin]

Great! I'll keep this in mind for the future - I found this in the interim, for anyone else with a dell Optiplex 780:

http://mymamebox.blogspot.com/2014/10/the-ingredients-computer.html

The owner soldered two leads to the existing powerboard - i'll probably go this route to minimize wires being cut.

[JDFan]

Try this:

That is actually for using a PC power supply when it is not plugged into a PC -- ie. there is a wire in the 20 pin connection that senses if it is plugged into the MOBO and if it can not complete the circuit since it is unplugged the power supply will not turn on - so in order to use a PC power supply without using a PC you need to short the one wire (usually the only green wire in the set) to a ground source so that it passes the test and turns itself on.

So not really relevent here since the OP is using a PC MOBO so that plug will be plugged into the MOBO and does not need to be shorted.