On 6/22/2011 6:41 AM, SMS wrote:

I included binding posts for +5, +3.3, and +12 and -12. The -12 is there
for RS-232 ports only, that's why it's only 0.5A.

This is what I built: http://i52.tinypic.com/20zzeva.jpg

It's helpful to find an ATX power supply that also has a manual on/off
switch so you don't have to add one (a lot of ATX power supplies lack a
rocker switch for on/off since it's not really necessary). Also find one
that doesn't have an external fan bolted on top.

The #1 problem with these conversions seems to be forgetting to
reconnect the sense wires after you cut off the big connector (I made
this mistake). The sense wires are connected to the appropriate voltage
at the connector, and when you cut off the connector the sense wire is
no longer connected to the wire(s) providing the power. The supply will
come on for a second then shut down because it's not sensing voltage and
it doesn't know why (could be a direct short to ground in which case it
needs to shut down).