How to Start a Dead Motherboard




Okay, it might sound a bit hard to believe and I don't guarantee that it will always work (depends on how bad your motherboard's conditions are), but here is what worked for me (at least till now). When I plugged in the computer the led on the motherboard would light up, but when I would press the power button, nothing would happen; therefore I tried a little modification to the power supply and it worked till now. If you are interested, please move on to the next step.

Step 1: A Trip to Your Toolbox

So, what you need is basically quite obvious:

1) An old motherboard
2) A (preferably old) power supply
3) The rest of the parts to function with your motherboard

The tools you will need are basically these:

1) Wire cutter
2) (preferably) Soldering iron
3) Solder
4) Insulation tape or shrink tubing.

You might want a screwdriver in case you want to take out your power supply to easily work on it.

Once you have the above materials you can get started.

Step 2: Some Useful Knowledge

Before you start doing the actual job, it would be good if you understand a bit about how our trick works. If you are the kind of guy who just wants to follow the instructions and do it you could skip this step, but it would be better if you read it.

When you switch on the mains power to your computer (when you press the switch on your UPS, or insert the plug in a socket), the power supply gives a +5V supply to the motherboard for minimal functionalities, such as for the power button to work and for things such as Wake-on-Lan, etc. (you will also get the LED on), this power is sent over the purple cable. When the motherboard wants to switch on (for example if you press the power button) it grounds the PS_ON# cable of the power supply to the black cables, the PS_ON# cable is the green one. At this point the power supply switches on and supplies power to all the items in your computer, when the voltages are all stabilized, it sends the PWR_OK signal to the motherboard over the gray cable. When your computer shuts down and the OS sends the power off signal, the motherboard disconnect the PS_ON# cable from the ground and therefore your system will power off. So if you know your power supply works, but when you press the power button your computer doesn't start, you understand that it is you motherboard that is not giving the PS_ON# signal to your power supply. What I will demonstrate is practically how to manually send the PS_ON# signal to the power supply ourselves. If you want to know more about how power supplies work, you can see this two links which I found:

Step 3: Enough Talking, Let's Do It!

Before starting let me tell you that by following this guide you will void your power supply's warranty (that's why I said a preferably old PS), so if you are using a brand new one, please make sure you want to do this. What we have to do is actually quite simple (we also don't need to open the PS box), here are the steps to follow:

1) With the wire cutters, cut the GREEN cable coming from the power supply to the motherboard connector.

2) Cut one of the BLACK ground cables at the same height as you cut the green one.

3) If you are going to use the heat shrink tubing, insert it now on the end of the BLACK cable that goes to the motherboard.

4) Using the soldering iron, solder the two ends of the BLACK cable plus the end of the GREEN cable that goes to the POWER SUPPLY together.

5) If you were using heat shrink cover the joint and shrink the tube, or if you are using insulation tape, simply wrap the tape around the joint.

6) Cover the end of the GREEN cable that goes to the motherboard, we will leave that end disconnected.

7) Plug your power supply into the mains without connecting the motherboard and see if the fan starts to spin.

8) If the fan did spin, connect the PS back to the motherboard, make sure you have RAM, CPU, etc. in the motherboard, plug in the mains again and hope it will all work.

9) In case you don't have a UPS which you can switch off to cut the mains input, you can add a switch to the front of your computer to do so (see the next step).

Yeah, I know, the steps above sound a bit confusing, no? Then you can try following the pictures. If you still have trouble just leave a comment and I'll help you. :-)

Step 4: A Few Little Inconviniences

Okay, if you follow these instructions you should get your computer working, however as you might have guessed there will be a few inconviences. First of all you will not be able to control your computer through the front power button anymore (just consider that button weren't there). Second, features like Wake-on-lan, etc. would not work since the only way to power off your computer now is to cut the mains power. Third, when you are shutting down your computer the OS will not be able to power off your computer (since OSes are not capable of pulling out plugs :) ) so when the OS has finished shutting down you'll have to manually cut the power, like in the old days where you would get a message like "It is now safe to switch off your computer" except that here you don't get a message. When your OS finished shutting down, the screen should go black, so you know when to shut down the power. To make that task simpler, unless you have a UPS which you can switch off when you're done (like me), you might find it useful (actually I also found it useful) to add a switch to the front of your computer which will disconnect the green cable from being grounded, like shown in the second picture.

If you want to make the shutdown procedure more elegant, you can try disabling ACPI features in your OS or BIOS, in that case you will get a message saying "It is now safe to switch off your computer".

Wish you a good luck if you try this out!



    • Tape Contest

      Tape Contest
    • Trash to Treasure

      Trash to Treasure
    • Arduino Contest 2019

      Arduino Contest 2019

    18 Discussions


    3 months ago

    My mother board and power bottom is Orange, how can u help pls


    2 years ago

    How about shorting green and black wire from psu fro behind mobo ?
    Is there any risk ?


    2 years ago

    My problem in my old pc is quite related to yours, my old pc is automatically power on when I plug in to the ps box but there isn't post and display action happen.

    Can I apply this method? or what cause this problem to my pc?

    i really need help.. maybe you could give me some tricks and tips to fix my pc...

    Thanks a lot...


    2 years ago

    Works like a charm. I had an old-ish gaming desktop that I thought was toast but it comes in clutch as the only working computer left in the house, and hopefully will be up until I can get a new one.

    A few tweaks though ;

    1. You really don't need to cut at the same height, just putting it out there

    2. In my power supply's case, there was at least 10 black wires. Might be more helpful to say that any works, as they all should be grounded, as some may be confused

    All in all though, thanks for the guide, it was extremely helpful!


    2 years ago

    As much as I would like to try this, I have some questions before I lose a good PSU.

    Just one, I think.

    1. What kind of 'dead' do you mean in this instruction?

    2. Will this work if the motherboard doesn't go through POST(Power On Self Test)?

    1 reply

    Reply 2 years ago

    By 'dead' I mean that the motherboard does not respond to input from the front panel power button (i.e., when you press it, no fans spin up, etc.). Most motherboards have an LED on the board itself that lights up even before the power button is pressed, in my case that LED was lighting up as expected.

    I cannot guarantee that this will work for you, this is a hack that was successful in my case, but your motherboard may be damaged in such a way that this hack might not help.


    Reply 4 years ago on Step 4

    Some times, ghetto is the way to go. (That rythmed so well tho.)


    6 years ago on Step 2

    I don't know what is more mental; that I tried this with my lovely Corsair PSU, or that it worked a treat. Thanks so much! You saved me a good 100+ quid, have some cyber beer :)


    8 years ago on Introduction

    This mode just turn the power supply on , immediatly when you put AC power in it ... Ohh and yes , this is a ghetto mod.

    2 replies

    9 years ago on Introduction

    Have to add this to my list of last ditch hacks to try after the warranty has expired.


    Reply 9 years ago on Introduction

    Actually I don't know what might have caused the fault, but I have also another newer motherboard which also did the same thing, but I already replaced it and moved the CPU, RAM , etc. to the new board so I cannot try it on that board.