One gentleman has done a writeup on creating a variable supply from an ATX. http://hackaday.com/2010/12/09/atx-psu-turned-into-an-adjustable-voltage-bench-supp

One gentleman has done a writeup on creating a variable supply from an ATX. http://hackaday.com/2010/12/09/atx-psu-turned-into-an-adjustable-voltage-bench-supply/ http://hackaday.com/2010/12/09/atx-psu-turned-into-an-adjust... It might be a good starting point for a kit which doesn't require a modification of the power supply itself.