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Dummy load for a PC PSU 350W

  1. Mar 6, 2017 #1
    I have a 350 w PSU (PC) with 3.3, 5 and 12 v outputs.

    I want to create a dummy load so that i will remain on and output the correct voltage.

    However, i found online that a 10 ohm 10w resistor is needed such as this one :

    Can you kindly verify if i need one for every output ? (3.3, 5 and 12 v)
    Or i connect one end to a Positive 5v and on the other end ground and still can use all outputs ?

  2. jcsd
  3. Mar 6, 2017 #2


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    Staff: Mentor

    PC power supplies often have a minimum output current on one or more of the rails. The datasheet for the power supply should specify those minimum output currents -- have you checked for that yet?
  4. Mar 7, 2017 #3


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    2017 Award

    agree with Berkeman, there are those that are like that
    and a large majority have a Power On line that needs to be grounded before the PSU will start up and run

    ATX power pins.JPG

    just permanently ground the Power On line and the PSU should always start up and supply all rails

  5. Mar 9, 2017 #4
    Thanks alot for the answers, i have managed to install a resistor (6.8 ohms 10w) connected to a 5v output. managed to turn on with a switch on the green wire and ground. so far so good, switches on and off accordingly. Thanks
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