I was playing around with an old power supply, and I already know that shorting pin 14 to ground turns on the power supply. My dell only has limited bays to instal hard drives in. I was thinking about making an external HDD array just for fun. I could use an SATA card to connect the drives.

Anywho, now for the part that I am asking about. How would I short pin 14 on the power supply connector to ground using a serial cable? I know that negative voltage is "1" and positive voltage is "0" in a RS232 interface. If the data pin of the RS232 was connected to pin 14 on the other power supply, and the common ground was connected to a ground on both ends, would I send a value of "0" to change the PS pin to "HIGH"?

Hmm... this is more complicated then I thought. I would have to make a small circuit to controll the power supply.

EDIT 2: Well, I actually now think a micro controller would be the best choice. I will get something from parallax if I feel the need to experament.