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Cooling Fans remain on when computer is turned off

Discussion in 'Tech Support' started by Goatee, 16 Oct 2019.

  1. Goatee

    Goatee Well-Known Member

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    I have a dell optiplex 9020 that has an unusual problem.

    The unit works fine, powering on and running normally. No issue with stability and performs as expected.

    However, as soon as power is applied to the unit (i.e. power cable plugged in) the fans spool up to full power. The fans remain on 100% until the power button is pressed, following which they spin down and act normally.

    I have updated all drivers and bios, tried disabling C-states and changing any remoterly appropriate bios options.

    Anyone got any ideas?
     
  2. The_Crapman

    The_Crapman Don't phone it's just for fun.

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    A) Haunted
    B) Malfunctioning turbo timer
    C) Malfunctioning PSU

    Any idea how it's wired?
     
  3. Shirty

    Shirty Time travelling rogue Super Moderator

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    Reset CMOS? Flash BIOS?
     
  4. RedFlames

    RedFlames ...is not a Belgian football team

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    This is more or less the troubleshooting step for macs when they do the same thing [which is often].
     
  5. Goatee

    Goatee Well-Known Member

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    Im thinking A, possibly C.... not sure what B is.
     
  6. Goatee

    Goatee Well-Known Member

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    Tried both, no change
     
  7. RedFlames

    RedFlames ...is not a Belgian football team

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    it's something that keeps the car engine running to allow the turbo time to cool down properly, avoiding damage. - linky: https://en.wikipedia.org/wiki/Turbo_timer

    In a pc context some PCs/PSUs keep the fans spinning for a few minutes after the pc shuts down to aid cooling.
     
  8. Shirty

    Shirty Time travelling rogue Super Moderator

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    Does the issue occur without the boot drive connected?
     
  9. Goatee

    Goatee Well-Known Member

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    Yep, its weird. More I think about it must be PSU.
     
  10. Goatee

    Goatee Well-Known Member

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    Ah, makes sense. Still think its haunted.
     
  11. yuusou

    yuusou Well-Known Member

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    Are the fans hooked directly to the PSU or to the board? If former then if the PSU sends out power regardless of motherboard, that'll be the reason.
     
  12. Goatee

    Goatee Well-Known Member

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    Board, separate headers
     
  13. yuusou

    yuusou Well-Known Member

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    There has to be some weird ass bios setting then. Or perhaps even a jumper.
     
    Goatee likes this.
  14. Goatee

    Goatee Well-Known Member

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    bios setting have been fiddled with but a jumper is a new angle! Will see if I can get the usff 9020 motherboard layout and see if a jumper needs tweaking!
     
  15. RedFlames

    RedFlames ...is not a Belgian football team

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    The Bios for the 9020 has a setting called 'Fan Control Override', which if enabled, cases the fans to go at full tilt all of the time. It's in the 'Power Management' section.


    ...source - R-ing TFM [Page 37]
     
    Last edited: 16 Oct 2019
  16. Goatee

    Goatee Well-Known Member

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    Tried that. It only impacts when the PC is turned on.

    It just makes the board sound the same when powered on and off.:wallbash::wallbash::wallbash:
     
  17. Nealieboyee

    Nealieboyee Packaging Master!

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    Is the CMOS battery still good? Holding the date and settings in the BIOS?
     
  18. Goatee

    Goatee Well-Known Member

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    Yep, battery is fine.
     
  19. veato

    veato I should be working

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