I have several old computers with perfectly working power supplies. I decided to convert one of them into into a bench power supply. Typically, a bench power supply can cost anywhere from $100-200 dollars or more, depending on brand and quality of equipment. With this modified ATX bench power supply, it cost me only $20 and about 3 hours of project work.

This ATX bench power supply gives me 3 different voltages at 3.3, 5 and 12 volts. The voltages are rated at 18, 12 and 21 amps respectively. I didn’t bother using the -5 and -12 volts since the amperage on these two voltages are very low. The only downside to this power supply is the voltages are fixed. It would have been nice to have an adjustable voltages.

It was a fun little project. I won’t bother posting the instructions since many people have already covered this topic. Here are two good sources worth checking: JumperOneTV and GeoNoJRJ.

Parts total at around $20

  • Binding Posts
  • Power switch
  • Lamp assembly
  • 10 ohm 10 watt load resistor
  • Heat shrink
  • Cable ties
  • Rubber feet