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Power reset now, PC won't turn on at all

By Ethan90
Feb 10, 2011
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  1. About a week ago, I came home and my clock was blinking 12:00 and my PC I had left on was turned off (a mild storm passed by). Now my PC won't turn on anymore, no fans, no lights, no sounds.. nothing.

    Things to note:
    1) Yes, I checked to make sure the PSU switch was on and plugged in. I tried different outlets.,
    2) My PC was plugged into a power strip during the "storm" (not sure how much surge protection that provides)
    3) No visible burn marks on my hardware
    4) I bought a new power supply because the PSU was my first suspect since it was 20 pin and I needed a new a 24 pin to fit my motherboard best anyways. ---No luck with new PSU---
    5) I figured it might be my front panel power switch, so I tried bypassing it by using the reset button as the on/off power sw. I also tried touching the on/off pins lightly with a screwdriver ---No luck---
    6) I've tried naked booting, with just mobo, cpu, and video card.
    7) I've tried 3 different computer power cords.
    8) When I turn on my new PSU I can hear it begin a very soft hum (like a capacitor charging or something) so power is getting to the PSU.
    9) I've tried booting with both 110V / 220V PSU settings
    10) I've tried taking out RAM and reinserting
    11) Idk if this is relevant, but my drive data cables are very old.
    12) My computer is basically new... new cpu, new mobo, new ram, new PSU.


    My best guess is that it has something to do with the front panel power switch. Any ideas? Please help. Also, I put up my PC specs in my profile let me know if you can't see them.


    Thanks,

    -Ethan
     
  2. GameJunkie72792

    GameJunkie72792 TS Maniac Posts: 357

    We just had a nice line of storms come through a few weeks ago.

    I was extremely busy replacing motherboard and PSU combos on various customer computers, mind you after having fixed them, I STRONGLY recommended they buy a decent surge protector.

    Turns out all but one were running straight out the wall.

    I've come across one scenario where the motherboard survived a PSU failure, luckily for me that was mine about a month ago.

    Generally a PSU fails, it takes the motherboard with it, if you have any other motherboard that will jive with your hardware, swap it out.
     
  3. Ethan90

    Ethan90 TS Rookie Topic Starter

    Thanks for the reply.

    Do you think that the motherboard is the only thing damaged? Do cpu's and video cards normally survive surges?

    Also, is there any way I can test my motherboard with a voltmeter before I buy a new one?
     
  4. robin_bga

    robin_bga TS Rookie Posts: 258

    Hi,
    Before you buy another one make sure u remove it out of the case, run it without any thing else connected, not even a graphics card, to see if it powers also you could test the PSU by shorting the GREEN and BLACK wires, if it spins the back fan, then know it ok...
    Hope that help bro
     
  5. Ethan90

    Ethan90 TS Rookie Topic Starter

    Okay, I haven't taken my motherboard out of the case and tested it yet (curious how that will help) but 2 things:

    a) The power strip I was using during the black out reads "Surge Suppressor"
    b) I tested both PSUs by using an old wire to connect pin 15 & 16. They both turned on. This means that my old PSU still works, right?

    Because of a) and b), I'm really doubting that my computer received a power surge that fried my motherboard. If that was the case, wouldn't my old PSU be fried as well?

    Because I want to rule out my power button, what is the best way to bypass the power button and manually turn on a computer?
     
  6. Appzalien

    Appzalien TS Rookie Posts: 96

    Forget the power button, its just a break in the wiring to momentarily make contact for power on, and would not be effected by a storm power surge. If the new supply still doesn't power the board it may be damaged. Just cause connecting pin 15 and 16 turns the old power supply on ( wires for the power on) doesn't mean that all the lines are functioning. You have 12 volt 5 volt and 3 volt lines, and if any one goes out, the board will not function.

    Since you tried a new supply, the only way to check your old one is to buy a power supply tester. Antec makes a nice one and they're not expensive. Motherboards can be tested, but short of the above mentioned pulling the board and adding devices one at a time, its much too expensive to go buying a mobo tester if your not going to go door to door making money with it. A Volt Ohm meter would do you no good unless you knew what voltages to expect at certain test points.

    You can check your old supply with a volt ohm meter, but its nice to have a diagram of the supplies colored line voltages. The negative of the meter would go to any black, and the different colors would give 12, 5, or 3 volts with the 15 and 16 pins connected so the supply is running.
     


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