Testing PSU / SMPS Working or Not With a Paperclip

Testing a PSU is the first thing what we check when we’re troubleshooting a dead computer and if you really having a dead computer on your side then there will be a 90% of a chance your power supply would be faulty.

To check a PSU outside from a computer is an easy task to do, you don’t need any technical or electrical knowledge to perform this testing thing, you’ll just need a screwdriver and a paper clip that’s it.

The simple testing method what I showed in this tutorial to test a PSU (power supply unit) will work on both type of SMPS either you have ATX or eATX model.

So Let’s See

Step 1 – Unplug Power Connections.

The first step is to do is unplug all the power connection to the computer and make sure your computer is turned off completely.

 photo trun off power_zps5ctyijd8.jpg

Step 2 – Open Computer Case.

Open your computer case by removing some of the screws at the left side of your computer case. You’ll only need to remove one side of a case:

 photo open case computer_zpsdvinxdmh.jpg

Step 3 – Unplug PSU Connection.

Unplug all the connection from the PSU (SMPS) to all internal hardware devices. Most of the connections contain clip attachment so make sure you lose the clip before removing any connection.

Make sure your SMPS/PSU isn’t connected to anything from inside:

Name of all connections to remove:-

  1. 24 Pin ATX From Motherboard.
  2. 4 Pin ATX From Processor.
  3. SATA Power Connector From Hard Disk Or DVD-R/W.
  4. 4-6 Pin Power Connector From Graphic Card (If Attached).

Step 4– Make A Shorting Wire.

After the SMPS connection was removed, make a “U” shape of the metal wire or you can use a paper clip by bending it to a “U” shape and that will help you to short your PSU to test, its working or not.

Step 5 – Test The SMPS.

First find the 20 or 24 pin ATX connector from your SMPS (obviously the bigger one) and after that locate the green and black wire connection. You don’t get confuse because there is only one green wire available in that whole socket.

 photo psutesting-min_zpsxr3drhjp.jpg

After finding the connection, attach the power cord to the SMPS and insert the metal wire into the green and black wire connector and short the circuit and that will allow us to test our SMPS/PSU is working or not.

 photo psu testing example-min_zpseraxg3p0.jpg

If the SMPS fan runs perfectly without any of lags and stoppage that mean your SMPS is working fine. If your fan doesn’t move or maybe move for just a sec and then stops that mean you have a faulty SMPS by your side and you’ll need a replacement.

 photo final test result-min_zpsp3i2m7q2.jpg

Advance testing

Smooth running PSU fan while testing doesn’t prove your PSU is working perfectly and it can only prove that there are 90% of chances your PSU is in working condition.

To properly check your power supply you’ll need an electric Multimeter which can show you, does your SMPS are giving right amount of dc power supply according to the every color code based wires or not, because every wire have its own voltage and by the use of Multimeter you can easily find your PSU is generating correct amount of electricity or not.

To test it, you’ll need a paper clip and a Multi-meter so makes sure you have these:

Step 1 – Set your Multimeter to the dc mode.

Step 2 – Turn on your PSU by attaching that paper clip or metal wire to the green or black wire slot, what I’ve also mentioned above for shorting.

Step 3 – Now test the every single colored wire square socket according to the voltage chart given below.

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    up to date like this. Thanks for sharing.

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