is blowing down unto something going to cool it better than blowing away?

Discussion in 'General Hardware' started by death_samurai, May 12, 2010.

  1. death_samurai

    death_samurai Ancient Guru

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    I notice that most stock cpu fans all blow unto the cpu but those 3rd party coolers instead have a giant heat sink and the fans face away and blow away from the heat sink.

    Which one is better?

    Blowing away or unto something?
     
  2. hartofalyon

    hartofalyon Ancient Guru

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    fans are suppose to blow on the heatsink. do you have an example of a 3rd party cooler with a fan blowing away from the heatsink?
     
  3. Passion Fruit

    Passion Fruit Ancient Guru

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    lol /facepalm.

    Theres a difference between the stock coolers, which don't use heatpipes, and aftermarket ones that do.

    Without heatpipes, the heat goes directly into the fins, and often they're too small to have a fan facing any direction but down. Either way, in this case, down is the more efficient solution as it clears the heat from the fins.

    Saying that, i've never ever seen a cooler that blows air away from the piece of hardware it's supposed to be cooling, that's just stupid.

    With heatpipe coolers, the heat is transferred into the heatpipes and then into the fins, and the fans blow it away. Obviously blowing on to something is going to provide better cooling in any situation.

    How is blowing air away from something going to cool it down? You need to blow cold air on to something to cool it, not hot air away from it.
     
  4. IPlayNaked

    IPlayNaked Banned

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    As long as the heatsink is designed properly, I see no reason a fan couldn't be pulling air through the sink.

    Rads can be set up to pull air.

    I mean, you're moving the same amount of air over the same fins either way.
     

  5. Passion Fruit

    Passion Fruit Ancient Guru

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    That's true, but there's coolers even without "fins" of the technical sense. Blowing air away from a component you're cooling won't cool it, of course if you're pulling air through cooling fins, it's still doing a job as long as the air is moving through them. I think he's talking about coolers which aren't suitable to even be passively cooled, like the stock intel heat sink which has a fan facing down... if you face the fan upwards to blow air away from it, you'll probably increase temps massively.

    Put a fan on a northbridge, you have it facing down so the air can cool the heatsink, you don't have it facing upwards because it won't do jack ****... lol
     
    Last edited: May 12, 2010
  6. ShadowMyth

    ShadowMyth Ancient Guru

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    It really just depends on your setup.
     
  7. Julepalme

    Julepalme Master Guru

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    Not entirely true..

    Yes you will have the same volume of air moving through the heatsink.. assumming you have a proper design etc..

    Assuming you have only 1 fan.. theres still the tiny pressure differences.. positive or negative pressure when blowing or sucking air through a heatsink.. and the general pattern of the airflow (turbulence etc)..

    But more often what you will see on more expensive heatsinks is a 2 fan system.. 1 blows 1 sucks.. attached to either side of the heatsink... theres probably a lot of trickery involved to optimize that aswell..


    Generally though its a proven concept today that blowing air at something cools it a hell of a lot better than sucking air away from it.
     
  8. TruMutton_200Hz

    TruMutton_200Hz Ancient Guru

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  9. death_samurai

    death_samurai Ancient Guru

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    oh yes i di thermaltake, megahalems etc etc they all don't have the fans blow unto the cpu.
     
  10. hartofalyon

    hartofalyon Ancient Guru

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    i just took a look at all the thermaltake coolers on newegg and they all have the fan blowing on the heatsink. i'm not sure if you're confused about the orientation of the fan relative to the cpu vs the heatsink. the ones with the vertical fans are still blowing on the heatsink, which is correct.

    heat is transferred from the cpu to the heatsink (fins) and the fan blows on these fins to whisk the warm air away, effectively cooling them down so they can accept more heat from the cpu and maintain a low constant temp.

    i have yet to come across a cpu cooler with the fan sucking air from the heatsink. if there was, it would be an improper/ineffective design.
     

  11. gurusan

    gurusan Master Guru

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    it really doesn't matter whether it's blowing or sucking, what matters is turbulent airflow across the fins. Whether blowing or sucking is the best depends on the heatsink design and where the fan is positioned.

    That said, most fans operate better when in a push configuration.
     
  12. naike

    naike Ancient Guru

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    There are aftermarket coolers that blow air sidewards.
    The heatsink is horizontal to the motherboard and the fan blows either to the back of the case or the front, supporting airflow.
    I have one and it works pretty well.
     
  13. Passion Fruit

    Passion Fruit Ancient Guru

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    I think hes actually asking, why don't the fans actually blow onto the copper block (onto the CPU) as opposed to blowing through the fins... lol
     
  14. Pill Monster

    Pill Monster Banned

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    I have Thermaltake CPU cooler and it blows onto the heatsink.

    The only fan I've ever seen suck air across a heatsink is a PSU fan..


    Analogy: If you burnt your finger, would you try and suck air across it to cool it off? Probably not - you'd blow on it right...?
     
  15. naike

    naike Ancient Guru

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    Put your finger inside your mouth, what would you do then?
    Basically, as someone stated above, it doesn't matter which way it blows, the airflow is important.
     

  16. morbias

    morbias Don TazeMeBro Staff Member

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    Pretty sure he's asking the difference between a top down HSF and a tower HSF.
     
  17. Nbz

    Nbz Master Guru

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    Ok, this thread confused the crap out of me.

    I'm pretty sure my Stock CPU Cooler which is attached to the Heatsink (Cooper/Silver Block) is blowing air OFF the block and not ON to it.

    Am I just totally off whats being discussed here or is my Stock CPU Cooler just retarded?

    Something like this

    CPU - Heatsink - Fan - AIR>>>>>>>>>>>>>
     
  18. Estima8tor

    Estima8tor Ancient Guru

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    Should be like this:

    CPU - Heatsink - <<<<<<<< AIR - Fan
     
  19. Nbz

    Nbz Master Guru

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    Yea it makes sense to cool down the pins from the heatsink fins but mine seems to be doing the contrary..

    Ill confirm it later, need to confirm 100% if the air is being exhausted or pulled in. If I put my hand it feels like its being exhausted..
     
  20. Pill Monster

    Pill Monster Banned

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    Q: Why do the trees in Pennsylvania lean west??

    A: .........
     

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