Heatsink touches PSU case, any problems?

Discussion in 'OT Technology' started by theanomaly, Apr 21, 2008.

  1. theanomaly

    theanomaly Active Member

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    A buddy of mine just put together his new computer and his blue orb heatsink fins touch the power supply metal case on the top. Could be a dumb question, but will there be any chance of him have short circuiting issues... I could care less about the air flow.
     
  2. trouphaz

    trouphaz New Member

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  3. Chris

    Chris New Member

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    The main forum is good for quick answers but sub forums will usually have more accurate advice

    I dont see a problem with it, with the double posting that is, you may want to see if you can bend any of the fins on the heatsink so they arent touching, better safe than sorry
     
  4. redfred18t

    redfred18t New Member

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    can you trim the fins?
     
  5. Doomsday

    Doomsday XXX

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    no short. i don't think you'll get temp problems either as long as you have good air circulation in that area.

    one other problem that could happen is that both will amplify vibration from fans, making an annoying noise.
     
  6. P07r0457

    P07r0457 New Member

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    you don't want it touching. can lead it vibration issues, as well as grounding.
     
  7. aim2kill

    aim2kill New Member

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    avoid if possible, sound/vibration=bad, but both should be grounded, so there should be no problems with shorting
     
  8. deusexaethera

    deusexaethera OT Supporter

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    Technically, there should be fewer grounding issues if the heatsink touches the PSU; otherwise, the only metal-to-metal contact the heatsink will have is through the CPU, which is not the safest thing, especially when the air is really dry in the winter.
     
  9. P07r0457

    P07r0457 New Member

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    a circuit needs TWO contact points. It already has one through the CPU... Don't give it a second through the PSU.
     
  10. deusexaethera

    deusexaethera OT Supporter

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    If either one had electropotential, yeah, it would be an issue. But the top of the CPU die is grounded, and so is the PSU chassis.
     
  11. P07r0457

    P07r0457 New Member

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    EXACTLY. Both are grounded, so connecting the two creates a potential path for electricity. Remember that, contrary to popular belief, electricity takes ALL paths relative to their resistance... not just the one path of least resistance. CPUs are very sensitive... And it doesn't take much to interfere with them.


    People think that being "grounded" makes them safe. It's the opposite. Lineman are able to work on live high-voltage carrier circuits because they are NOT grounded. If they become grounded, death is the usual result.
     
  12. deusexaethera

    deusexaethera OT Supporter

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    Yes, electricity does take all paths, inversely-relative to the resistance of each path. I'm not disputing that. But unlike your example of the electrical worker, the PSU and the CPU die are connected to the same ground, so while electricity can be conducted from one to the other, there's no voltage differential to drive current.

    Meanwhile, in a dry environment, the fan can cause a buildup of static electricity on the heatsink, and while the CPU die can conduct that static to ground, like you said, electricity will take all paths to ground, including through the transistors in the CPU. Whereas, if the heatsink is grounded directly to the case as well, the combination of the low-resistance connection to the case and the high-resistance connection through the dielectric grease and CPU die means that the vast majority of any static buildup will go straight to the case instead of through the CPU.
     
  13. P07r0457

    P07r0457 New Member

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    Incorrect. The same ground plane at differnet points will have different potential.

    Then why are HSFs not usually grounded using a grounding strap to the chassis. Because it's a BAD IDEA.
     
  14. aim2kill

    aim2kill New Member

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    SLUGFEST!
     
  15. deusexaethera

    deusexaethera OT Supporter

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    In theory, the same ground plane will have different electropotential at different points, but it depends on the conductivity of the ground plane. In this case, the conductivity is so high, and the distance is so small, that any GVD will be negligible even compared to what the CPU transistors are used to dealing with. If the case were made of damp soil, on the other hand, then the GVD between two points could become significant.

    Heatsinks aren't usually grounded because that would make it too complicated, not because it's a bad idea.
     
  16. Doc Brown

    Doc Brown Don't make me make you my hobby

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    Well since every part of a computer shares a common ground, the only way anything bad could happen would be if there was some sort of psu meltdown that made the case go hot instead of being a ground point.
    But if that happened, it would likely fry everything anyway.

    Vibration is another issue. If for some reason there was vibration as a result of this, that could potentially cause problems with the cpu.

    Anyway, it would be easy enough to just trim the edge of the fins with tin snips.
     
  17. deusexaethera

    deusexaethera OT Supporter

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    Or a bench grinder.
     
  18. P07r0457

    P07r0457 New Member

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    :hsugh:

    sorry, i forgot arguing with you was like arguing with a deaf, dumb, and blind child... I forgot you think you know more than intel's engineers. :ugh2:
     
  19. CodeX

    CodeX Guest

    grounding? are you serious? :rofl:

    You just make up stuff don't you? Last I knew neither the PSU case or the body of the heatsink carried a charge, therefore they are both grounds already, therefore connecting them will not make them more or less of a ground... (since grounded is grounded... there is no levels of it)

    There won't be any thermal issues either since both of these two devices have fans attached to them... if anything it will simply regulate the two devices so that they are closer in temperature, acting as one object instead of two.

    Vibration and noise may be an issue though and is the sole reason why I wouldn't want them touching.
     
  20. P07r0457

    P07r0457 New Member

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    go read NEC. It was updated for 2008... But the knoweldge I have gained from it is found in many editions in the past. You can pick up an "ugly reference book" if you want a sort of cliff-notes instead of the full thing.

    It is very obvious that you are simply an amature.
     
  21. dorkultra

    dorkultra OT's resident crohns dude OT Supporter

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    here we go again...

    just fucking trim the fins and delete this thread so they can stop panty slapping
     
  22. redfred18t

    redfred18t New Member

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    thats what I said

    do that and its a done deal
     

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