Power supplies

if that is the case the atx has what you call soft power unlike AT power supplyes. which means that the board always has power and there for the ATX does what is called a soft boot where as even though the power is off the mother board has power to do this the power swich hooks in to the mothere board va jumpers i am not sure where the jumpers are found on your board though for the pin out. but it should be found around the place where you have all your leds pluged in to the board

There was some recent discussion about this on another thread. The general conclusion was that attempting what you are attempting is an extremely effective way to fry your motherboard and set your building on fire.

Maybe you can get it to work.It all comes down to how dangerously you want to live.

An ATX MB has the On/Off power switch plugged into the MB, not the PSU. If your MB "supports" the ATX PSU then it too should have a couple of pins to connect your On/Off switch from your case. If you can't find these pins (often near where the case LEDs and speaker connect) have a look at the MB OEMs website.

I'm sure there's also a kluge, but it sounds like a fine way to test your sprinkler system.

For the cost of a new PSU, if you can't see straight away where everything plugs in, buy a straight replacement. I f you do mess about with it, make sure you do not need the computer for some time in case it all goes pear shaped.

The power switch on an AT case isn't the same
type as the switch on an ATX case. I'm not
sure if you can change the switch, but it
would be easier to buy an AT power supply &
replace the broken one.