Introduction: DIY Bench Power Supply With Old Computer SMPS

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Hey! everyone My name is Steve .

Today i'm going to show you How to make a Bench Power Supply With Computer Power Supply

Bench Power supply is very useful in electronics field it is very easy to make it with a regular ATX power supply

Click Here to See The Video

Let's Start

Step 1: Features

Supply Output

  • 3.3 V @ 30A
  • 5 V @ 25A
  • 12 V @ 10 A

it's my specification all it's depend upon your power supply power output


  • Green Led ( power indicator )
  • Toggle Switch (On/Off)

Safety Features

  • Short circuit Protection
  • Over load Protection
  • Over Heat Protection

All this Built in your ATX Power Supply

Step 2: Stuff I Used

  • SMPS
  • Binding post click
  • Led with 220ohms resistance
  • toggle switch

Step 3: Opening

Open 4 screws from the top ( see the picture )

Step 4: Drilling

  • Mark the position for drilling with a marker ( see the picture )
  • First Drill with small drill bit and then go for bigger
  • Drill total 8 holes ,6 for binding post , 1 for led , 1 for switch

Step 5: Installation

  • First start with installing the binding post ( see the picture )
  • then install the led
  • and then install the switch

Step 6: Connection Led & Switch

  • First cut green and black wire and solder them on the toggle switch ( see the picture )
  • And then cut orange and black wire and solder with a 220 ohms resistance on the LED

Step 7: Cutting

  • Cut 3 Yellow & 3 Black , 3 Red & 3 Black , 3 Orange & 3 Black wire
  • Cut the Length to reach all the connection
  • Don't cut too small


  • Yellow wire gives you 12 V
  • Red wire gives you 5 V
  • Orange wire gives you 3.3 V

Step 8: Wire Grouping

  • Twist the 3 wires and make a bunch ( see the picture )
  • Do The same with all the wires
  • To make it looks less messy

Step 9: Connect

  • Connect those 6 wire to the binding post and tighten the nut ( see the picture )


  • Yellow & Black - Black And Red Terminal of first Group
  • Red & Black - Black And Red Terminal of Second Group
  • Orange & Black - Black And Red Terminal of Third Group

see the picture for more information

Step 10: Cutting

  • Trim off the unused wire ( see the picture )

Step 11: Securing

use a cable tie to tie loose wire ( see the picture )

Step 12: Closing

Now close the cabinet and tight 4 screws

Step 13: Finishing

Now mark the terminal

  • First binding post 12V
  • Second binding post 5V
  • Third Binding post 3.3V
  • Led
  • Switch (On/Off)

Click Here to See The Video

You Just Made It

Now just Plug the power and enjoy

Thank you for visiting my Instructables

Stay tuned for next Projects