Question about System Power Supplies

1 Answer

Diagnosis PS only works when "TEST"button is held

Posted by on

1 Answer

  • Level 2:

    An expert who has achieved level 2 by getting 100 points


    An expert that gotĀ 5 achievements.


    An expert who has answered 20 questions.


    An expert that hasĀ over 10 points.

  • Expert
  • 103 Answers
Re: Diagnosis

Some power supplies have a microswitch that prevents a turn on while the case is open. Sometimes it's a switch on the case, or a switch linked to the mobo. You can try to defeat that. Also PSU's are made so they won't turn on unless hooked to a mobo. You will have to jump some pins to defeat that. This info is readily found in Google.

Posted on Jan 04, 2008

Add Your Answer

0 characters

Uploading: 0%


Complete. Click "Add" to insert your video. Add


3 Points

Related Questions:

1 Answer


Plug into motherboard, turn on computer.....(you dont need it in computer to test just pins)
Or you could buy a Power supply test device

May 17, 2012 | Compaq PS-5500-1C (244163001) 50-Watt...

1 Answer

I have an Antec Truepower 2.0 TPII-430. This power supply provides power to the fans but when I push the computer power-up button, nothing happens. I installed another similar power supply and everything...

Test it. Unplug the molex connector from the mothrboard. You can use a wire or a paper clip to test it to power on. You will connect (short) pin 14 to and ground pin. (diagram here) For example, put one end of the paper clip into pin 14, and the other end into 13, 15, or 16. If the power supply turns on and fan running then maybe a problem with the front panel switch on the computer case.
P.S. make sure you unplug all other leads to drives before doing this.

Apr 06, 2011 | Antec : True430 430W P4 ATX Power Supply...

1 Answer

No power supply power out, ps fan not coming on, fuse is good

Test your PSU or replace it if your power supply units fan is not working your PSU is faulty

Dec 30, 2010 | Gateway Emachine Bestec ATX-250-12E PS...

1 Answer

5 yr old Asus with antec 450 power supply has had NO issues ever. Now I need to turn the ps off and on 2 or 3 times before the start switch at the front of the comp will work.... once it boots up...

there are several filter capacitors inside the power supply that are defective and /or are changing value. this accounts for the high pitch squeel you are hearing...the only REAL way to test for these problems are with an esr meter or lcr bridge, but you can physically look at the capacitors and see if any of them are bulged up or leaking., my suggestion is to go to and get another 450W or better PS...they are pretty cheap there

Dec 27, 2010 | Antec SP450 450W SmartPower ATX 2.0 20/24...

1 Answer

Gateway yellow power button, nothing starts, no fan, nothing. opened up computer and see mobo led light is lit. newton ps has a test button. tried to test with various components plugged in and the test...

Power supply has several voltages. Just because the 5v power is active doesn't mean all the voltages are OK. You need to have the power supply tested for 12v and 3.3v. A quick test is to unplug all the wires from the power supply. There is a single green wire on the motherboard main plug. Connect (use a bent paper clip) that green switch wire and any black wire. Plug in the power supply and it should run (fan starts)

Oct 26, 2009 | Gateway (ATX-300-12EB3) (ATX30012EB3)...

1 Answer

My wife has an eMachines T1600 in her first grade classroom. It worked in June when class ended, but does nothing now when we push the on button. I suspect the Bestec ATX-250-12E power supply, since...

Hello there martinsjak.

Here's your GEEK-steer ...

First, I'll presume you have of course "lamp-tested" the wall power outlet, as well as the power strip outlet you using, and that also the power cord is in good repair.

With that out of the way, kudos are in order, because your suspicion of the Power Supply Unit (PSU) is very well founded. It is THE most common PC component to fail. Although it could also be the case power button/switch itself, it's likeliest to be the PSU. But regardless of which, the easiest way to find out is to test the PSU.

You have three options:
  1. Manually test it using a multimeter ... Yuk! Only a guy with a plastic pocket-protector (and thinks it's impressive) would pick this one.
  2. Install the suspect PSU into a KNOWN GOOD working PC. If the PC powers up, you know the PSU works. If not ... well you get the picture.
  3. Test it using a PSU Tester. This is a surprisingly desirable option. Why? Because PSU testers are not very expensive, and if you're like most everyone else in this modern era, you'll be in need of testing more than just this one over the course of time. Check out this very solid choice for a Coolmax PS-224 ATX Power Supply Tester.
Which of the above three is your call. Easy-peasy, yeah?

Good luck to you, and thanks for posting back ...
  • to let me (and others) know how things worked out,
  • if you have any further questions,
  • to provide clarification or feedback.
"Today's the best day of my life ... and NOW you're part of it!"
Via-con-Dios and Godspeed -- Craig

Sep 25, 2009 | Gateway Emachine Bestec ATX-250-12E PS...

1 Answer

Computer does not turn on

you can try your power supply if it works by jumpering its pin. try to insert copper wire in pin 11 and connect it to pin 12. and turn o your power supply. But if it won't works then used tester and test its circuit boards particularly  is capacitors, resistors and even the transformer inside the power supply. Or if you can't make it then you can call a technician either in computer or electrical to test your power supply if it still working or not. In that wy can be sure in making decision if its really your power supply got problem or not.


Jun 26, 2009 | Lite On (PA41519B1) 150-Watt Power Supply

1 Answer

A PS-5022-2DF Power Supply

When a power supply goes bad they are generally not worth repairing given the low replacement costs these days.
I have bought a lot of replacement Dell power supplies from this place over the years.
Remember a lot of Dell power supplies and motherboards are proprietary so you cannot use generic parts.

Aug 11, 2008 | Dell (9228C) 200-Watt Power Supply

1 Answer

Dell power Supply has won't work

Hi, all power supply's have a fuse in them, remove the power supply, open it up and study the printed circut board, you will see either a white ceramic or glass fuse attached to it. Replace this and reasemble it then re-install it into your computer and then test it. If you still have no power then you will have to replace the unit as the costs of repair are far greater than a new one. Goodluck, mistyman

Aug 30, 2007 | Dell POWER SUPPLY PS-5201-5D (PS52015D)...

Not finding what you are looking for?
System Power Supplies Logo

Related Topics:

128 people viewed this question

Ask a Question

Usually answered in minutes!

Top System Power Supplies Experts

Brian Sullivan
Brian Sullivan

Level 3 Expert

27725 Answers


Level 3 Expert

5660 Answers


Level 3 Expert

18258 Answers

Are you a System Power Supply Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides