What are the steps I should take to trouble shoot my computer not turning on?

by on August 4, 2009

Q: What is the best way to troubleshoot a PC that won’t turn on? Power Supply is brand new, MB is a year old. I hit the button, hear a small, short whir (it’s not one of the fans) and then silence.

9 Responses to “What are the steps I should take to trouble shoot my computer not turning on?”

    It comes down to process of elimination, a few possibilities:

    Problem with motherboard
    Problem with Power Supply
    Loose wire
    Problem with the power button

    If the power supply is brand new, do you still have the old one? Did you swap out power supplies because you thought that was problem?

    The power supplies can be tested independently of the rest of the system. Try completely removing the PSU and unplugging it from all the computer components, and then following these directions: http://www.techpowerup.com/articles/other/22 There should be a bunch of how to videos around youtube as well if you want some additional instruction.

    This way you can test to make sure the PSU is functional. (Naturally, all of this involves electricity, which can kill or hurt you, so please observe all normal precautions. Don’t do anything you aren’t comfortable doing, etc.)

    If the PSU works, it’s time to examine the rest of the system. Check for any electrical shorts ( anything metal that should be carrying electricity touching the metal of the case). You can also try booting the system with as little plugged in as possible. (Mobo/CPU/PSU/ a stick of ram, and some kind of data drive)

    This type of trouble shooting can be a huge pain because of all the variables involved. Good luck!


      I have ruled out the PSU….it was my first guess so I ordered a new one (that better fits my needs anyway) and neither the new or old ones seem to work. I get more of a reaction from the new PSU….that’s the “whir” I mentioned, plus there is an LED that lights when the power plug is connected to the wall and the master switch is flipped.

      I don’t know about any shorts and that’s kind of a laborious thing to search for but I will try that next.

      I have also tried booting with only my RAM, master HDD and video card, but no change. I will try only one stick of RAM.

      Is there an easy, cheap or free way to test if the MB is still functional? Or do I need special equipment or a hefty service bill?


    You can try removing the limited components you need to boot from the case, placing them all on a non-conductive surface and booting that way. With everything hooked up and the case taken totally out of the equation you can rule out shorts.

    To turn on the system without a power button, you can make a brief connection between the two PINS that the power switch from the case plugs into with a flat head screw driver.

    If you still can’t get the system to boot, I’d suggest contacting the mobo manufacturer for support/RMA, detailing all the crap you’ve tried.


    I wouldn’t have thought of bringing it out of the case…so simple….

    Do I need the video card plugged in?


    Unless it has on board video, yes.

    (just be extra careful doing this, I had a motherboard I was doing this with years ago slide onto some metal while I was testing it and it make a transistor glow red and smoke).


    unfortunately no onboard. Will keeping plugged in prevent it from turning on outright? I know the OS won’t boot without it, but I’m mainly looking to see if I can get this thing to just power up.


    Sorry, that sentence made no sense….will unplugging the vidcard prevent it from turning on entirely?


    I think it will turn on, and keep running but it won’t make it past the BIOS.


    Okay, it’s not much more effort to try it both ways anyways. Thanks for the help gentlemen. I’ll report back with results.