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How To Repair a Computer Power Supply (or other switching power …

How To Repair a Computer Power Supply (or other switching power ...

UPDATE: The big double Schottky diode has 2 anodes and 1 cathode. Sorry, I accidentally told it the wrong way around :).

In this video I show how to repair an ATX computer power supply and what are the most common failures. Most of these tips can apply to any switch mode power supply (SMPS).

Watch my previous video - How Does a Computer Power Supply Work:

Schematics of AT and ATX computer power supplies:

My ATX power supply tester:

You can support me on Patreon:

-This video is not intended for laymen.
-Computer power supplies contain hazardous mains voltage!
-Risk of electric shock and death.
-Risk of fire.
-Leave repairs to professionals.
-You do everything at your own risk and responsibility.


List your electronic components at

Tags: smps electronic components

About the Author


  1. Date: August 18, 2018 at 14:16
    Author: Jing Arjay87

    when one of the big cap fails, it usually brings the other one to death
    it happen to me yesterday

  2. Date: August 18, 2018 at 19:51

    My SMPS output fluctuates. But green and purple wire on standby shows perfect 5v. But 12v, 3.3v and 5v outputs fluctuates. What could be the problem. Please answer me.

  3. Date: August 22, 2018 at 03:34
    Author: Nick

    Where did you get that soldering iron from? Love your vids!!

  4. Date: August 23, 2018 at 22:07
    Author: dossip

    My last name is Layman, can I still watch this video ?

  5. Date: August 24, 2018 at 05:35
    Author: Bryan Chance

    Great video crash course in power supply trouble shooting. I especially like the detailed explanations with schematics and diagrams. Thank you. Your power tester box and the ATX tester is awesome!! Do you have a video on how to make them?

  6. Date: September 13, 2018 at 14:40
    Author: dre archon

    Hi I hope you can email me that handy diagram..thanks

  7. Date: September 18, 2018 at 19:53
    Author: Basil

    An excellent instructional video! I have learned more from this video about pc power supply trouble shooting and repair than I have watching many others! Well done, subbed.

  8. Date: September 26, 2018 at 00:46
    Author: Ello Oku

    My PC keeps restarting at times and when ever auto switch from our Country power supply to Inverter. It seems the power supply can't carry it anymore. Which part do I modify? I suspect the Capacitors.

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