I finally found the time to make my own bench top power supply from and old computer power supply. This has been done many times before and this is my take on it.

What you need

Computer Power Supply
Screw drivers
Wire cutter/Strippers
Ring terminals
Soldering Iron (If your right terminals aren't crimp type)
4 screw terminal posts (I made my own, Instructable here)
Heat shrink Tubing
Switch
Drill

And as always be careful around power supply's. They contain capacitors that can cause serious harm to yourself if not handled properly.

Step 1: Identifying Wires

For the first step we need to take the case off from around the power supply.

Now you need to identify the wires

YELLOW = 12 Volts
RED = 5 Volts
ORANGE = 3.3 Volts
BLACK = Ground
Green = Power On

I cut all the other wires back down to the board and wrapped the ends with black tape to prevent them from accidentally touching anything else.

I then sorted the yellow, red, orange and black wires into separate groups.

I set the green wire and one black wire aside for the switch to turn on the power supply.

Step 2: Adding Terminals

Now i selected around 6 wires from each color and trimmed the rest down close to the board and covered with black tape.

The six wires from each color were then soldered into a ring terminal and then covered with heat shrink tubing.

The green wire and the one black wire were wired into the switch.

I then attached my screw post terminals to the ring terminals.

Step 3: Drilling Holes

Mark out on your power supply case where you want your terminals and switch to be. (Since my power supply was smaller and more compact I didn't have much choice where they would fit)

Drill out your holes and test fit your terminals and switch.

Step 4: Button Everything Up

Put your post terminals and switch in there holes and reassemble the case. Now plug in power and test your voltages. You now have a cheap desktop power supply.

I would of liked to have added an led to signal when the power supply was turned on and this could easily be done with an led in series with a resistor connected to one of the voltages.

Thank you for taking the time to read my instructable, have a nice day!