A7V600 don't power up after CPU-fan remount

Discussion in 'General Hardware' started by Eproxus, Apr 21, 2005.

  1. Eproxus

    Eproxus Long gone and now back!

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    A7V600 don't power up after CPU-fan remount [SOLVED]

    {Hi,
    Today I thought I'd clean my CPU-fan which had gotten really clogged up with dust. After remounting it, the computer does not power up.
    This is what I did. First I unmounted it and removed the fan from the heatsink and then vacuumcleaned it properly, no liquids used. Then I remounted it:


    • Put it on properly (didn't apply new cooling paste though the old was dry, don't have more at the moment. Shouldn't be a problem with power up anyway).
    • Connected the power (it is one of those large four pin ones that are connected to the hard drives too).
    • Connected a little yellow cable to some pins marked CPU_FAN, guess this is the rpm counter for the motherboard.
    • Plugged the fan speed wheel cable back in.
    It was a really long time since I last modified the hardware. I reconnected every cable as it were before.

    Now when I connected all the cables back in the computer and press the power button, the fan speeds up and the power LED is lit. But after half a second the power up process is abrubtly stopped and the computer dies. The motherboard power indicator LED inside the box is lit all the time. The computer worked perfectly before. What is the problem and is there a solution?

    Any help is creatly appreciated! Can't wait to play World of Warcraft again...
     
    Last edited: Apr 23, 2005
  2. Xie

    Xie - geek - Subscribed User Folding Team

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    By "vacumed properly", what do you mean? What did you vacum? Also double check that everything is seated ok. Also do you get any beeps?
     
  3. gonaads

    gonaads Beware the G-Man Political User Folding Team

    Remove Heatsink/Fan assembly from CPU. Clean off old thremocrustyshiit. Get Arctic Silver thermo compound, apply as per instructions. Reinstall Heatsink/Fan Assembly. Reboot


    It sounds like the CPU is overheating and shutting down. That old thermocrustyshiit is prolly not conducting any heat whatsoever.

    It couldn't hurt. Also double check yer connections... the ones ya disconnected and then reconnected. Something could be loose or plugged into the wrong thing.
     
  4. Eproxus

    Eproxus Long gone and now back!

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    Thanks for the advice!

    I cleaned the heatsink with the vacuum cleaner, dusty as it was. No beeps whatsoever, that's why I'd figured it was some sort of power problem.

    I checked the connections as much as I could, and there didn't seemed to be anything wrong with them. Also, I had the fan turned to the maximum speed (5400 rpm or something) so the computer should at least boot up.

    The old paste probably does more bad than good in this case. Will try applying Arctic Silver as soon as possible. Thanks again!

    Edit: Oh, I also thought the problem might be that the motherboard somehow does not recognize the fan operating or misjudging the speed due to some cable being broken?
     
    Last edited: Apr 21, 2005
  5. gonaads

    gonaads Beware the G-Man Political User Folding Team

    The CPU Heatsink Fan has to be plugged into the "CPU Fan" plug on the MOBO. The plug has to be the one labeled for the CPU Fan. Otherwise the BIOS will think that the fan is dead and it won't boot, since it's trying to protect the CPU for melting.
     
  6. LeeJend

    LeeJend Moderator

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    Make sure the 4 pin plug for fan power is not in upside down. It's real easy to do on some plugs. Red, yellow and back wires should line up with the mating connector. Also make sure that no pins in the connector are pushed out through the back, it happens a lot also.

    Make sure the yellow fan speed cable to the MB is not plugged in backwards. You should not be able to plug it backwards but check anyway.

    Finally, do the fans spin up at all when you hit the power button? If not you've got more than a fan problem. You may have nudge the MB while changing the fan in and out shorting the MB to the case. Make sure the screw hole pads are centered around the MB screws.

    Also make sure you did not pull the power sitch plug out by accident while working in the case.
     
  7. Eproxus

    Eproxus Long gone and now back!

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    Okay, solved the problem!

    Solution. Removed heatsink and fan. Cleaned off old cooling paste. Applied Arctic Silver 5 according to instructions (didn't do such a proper cleaning as they recommended, didn't have access to all chemicals). Tightened all the motherboard screws, they were a little loose perhaps. Remounted heatsink and fan. Powered up good as ever.

    Thank you everybody who helped me!

    / Adam
     
  8. gonaads

    gonaads Beware the G-Man Political User Folding Team

    YEAH! :)






    Great to hear it.
     
  9. Xie

    Xie - geek - Subscribed User Folding Team

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    Glad to see you got it going. Could have been the cooling thing and CPU saving itself by not running, or could have been those loose mobo screws were creating a short. ;)
     
  10. Eproxus

    Eproxus Long gone and now back!

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    Thanks. :)

    Most likely it was the screws. I have a hard time believing it was too hot, it should at least have booted when being cold from beenimg off for a while.