Better to have 2 intake fans & 1 exhaust or 1 intake & 2 exhaust fans?

Discussion in 'Off Topic' started by Techie333, Sep 27, 2003.

  1. Techie333

    Techie333 Platinum Member

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    Building computer......got 2 possible configurations.......is it better to have 2 intake fans and 1 exhaust or 1 intake fan and 2 exhaust fans??
     
  2. Eli

    Eli Super Moderator<br>Elite Member
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    You do NOT want to create a vacuum in your case. If you do, your cooling efficiency will go WAY down.

    Optimally, you will have just as much air entering as leaving.

    So the answer is that 2 intake and 1 exhaust would be better than 2 exhaust and 1 intake, but 2 of each would be best.
     
  3. Rahminator

    Rahminator Senior member

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    Yeah, a dinky fan will create a vacuum... riiiight.
     
  4. Techie333

    Techie333 Platinum Member

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    ok....thanx.....only temporary.......will get another fan soon.
     
  5. Sundog

    Sundog Lifer

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    Don't forget to include your PSU fan when figuring out positve/neutral/negative air pressure/flow.
     
  6. DrumminBoy

    DrumminBoy Golden Member

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    hmm...i have 3 exhaust fans and only 1 small intake fan...think this is a bad setup?
     
  7. brigden

    brigden Diamond Member

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    WRONG FORUM! WRONG FORUM! WRONG FORUM!
     
  8. Vic

    Vic Elite Member

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    Not necessarily vacuum, but lower air pressure.

    Eli was absolutely right.
     
  9. Techie333

    Techie333 Platinum Member

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    PSU fan doesn't count, does it? Then I would have 2 exhaust and 2 intake.....
     
  10. Eli

    Eli Super Moderator<br>Elite Member
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    Yep, it definately isn't as good as it can be. With 3 fans exhausting air out of your case, the intake fan is most likely actually restricting airflow.

    Try reversing the setup and observe your temps.
    Yes, of course it counts.. as long as it is removing air from the case, it counts.

    Remember that you have to pay attention to CFM.. it may be difficult to determine the CFM of your PS fan... unless it's a well known brand or something.

    I just avoid all these problems by leaving my case open. ;)
     
  11. Abhi

    Abhi Diamond Member

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    Hehe :D
     
  12. Howard

    Howard Lifer

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    Tell you what: if you have more air coming in than out (calculate the airflow), you can accumulate less dust than if you had a partial vacuum inside. Just make sure you filter the intake, no need to filter the exhaust.