Results 1 to 12 of 12

Thread: Help me cool my MOSFET's!

  1. #1
    Registered User
    Join Date
    Oct 2005
    Location
    Serbia, Belgrade
    Posts
    69

    Question Help me cool my MOSFET's!




    I did vcore mod. Now MOSFET's on my MoBo are getting hot, realy hot. Any idea how to cool them?
    Did I cut some ZALMAN chip-set cooler and putty on MOSFET's, or mod some CPU Cooler...
    Biggest probelm, to me, is compact area. I can't just put one heatsink, must be in 3 part because of capacitors...
    I have all tools, (can buy) all heatsink's but I miss idea.
    Any suggestion?

  2. #2
    IT Engineer in the making
    Join Date
    Jun 2003
    Location
    Former Kingdom of Bavaria
    Posts
    2,094
    Buy a old (perhaps pin-style) CPU-heatsink and cut it into pieces. One heatsink per mosfet is the best idea. I wouldn't advise you to use one heatsink for more than one mosfet as contact will be worse (height difference between the fets) --> worse cooling performance --> lifetime of the fets will decrease. All you'll need is a hacksaw, a file, perhaps sandpaper, thermal epoxy and of course one big heatsink. Cheap and still very effective if done right.

    And don't forget active ventilation of the power regulation area, as the fets are designed to dissipate the heat into the PCB. This means only a part of the heat will travel into your heatsinks. The majority of it will spread into the area around the fets. That's why the fans will help much!

    BTW, you can produce your own thermal epoxy by mixing two component epoxy and thermal paste 1:1.
    Quote from one of our professors:
    "Reality is hiding in the imaginary part."

  3. #3
    Registered User
    Join Date
    Oct 2005
    Location
    Serbia, Belgrade
    Posts
    69
    celemine1Gig, thanx a very lot for suggestions!
    Your explain that MOSFET's dissipate the heat into the PCB give me one more idea:
    Maybe best option for me is to buy CM Gemin II? It will cool all what's around socket (including DDR)...
    Will than be need heatsink's on MOSFET's?

    One more question:
    I remove active cooling from "fets" on my second MoBo (GA-K8NSNXP-939) - it was too loud - and there, temperature is a fairly lower (this MoBo have 6-phase power unit) than on BIOSTAR (3-phase) from first post in this thread.
    What is about? Better quality "fets" on GA MoBo or number?

  4. #4
    IT Engineer in the making
    Join Date
    Jun 2003
    Location
    Former Kingdom of Bavaria
    Posts
    2,094
    Quote Originally Posted by SuperStarr View Post
    celemine1Gig, thanx a very lot for suggestions!
    Your explain that MOSFET's dissipate the heat into the PCB give me one more idea:
    Maybe best option for me is to buy CM Gemin II? It will cool all what's around socket (including DDR)...
    Will than be need heatsink's on MOSFET's?

    One more question:
    I remove active cooling from "fets" on my second MoBo (GA-K8NSNXP-939) - it was too loud - and there, temperature is a fairly lower (this MoBo have 6-phase power unit) than on BIOSTAR (3-phase) from first post in this thread.
    What is about? Better quality "fets" on GA MoBo or number?
    The GeminII could be enough, but I can't say that for sure. You'd have to try it on your own.
    About your 3 to 6-Pase difference question: I dare to claim that the Gigabyte seems to have the more efficient power regulation solution. It could be that the Gigabyte can generally deliever more power, thus it's not that stressed by your system, but I don't think that the difference is just the 3 to 6 phases. I am positive that you could build a motherboard with only 3-phase power regulation and still have cool running fets. The choice of parts and quality of the design/circuit is the key.
    Quote from one of our professors:
    "Reality is hiding in the imaginary part."

  5. #5
    Xtreme Enthusiast
    Join Date
    Oct 2006
    Location
    Atlanta GA - USA
    Posts
    843
    I say cut up an old AMD stock heatsink
    Heatware -> http://heatware.com/eval.php?id=51939
    Ebay -> http://myworld.ebay.com/onewhoisplug
    Feel Free to hop in my ventrio server and chat with us
    Vent6.gameservers.com:4498

  6. #6
    Xtreme Member
    Join Date
    Jun 2006
    Posts
    289
    I did exactly that and stuck it on my fx5700 modded to fx5950u. Voltmodded 2. Now stays @ 30c or lower @ uber speeds.

    It's quite easy, just grab a dremel or regular hacksaw and make little ractangles Take some as5 and some glue, as5 the heatsink to the mosfet and put 2 drops of glue on opposite sides (NOT betweent he heatsink and the mosfet, on the sides so that the glue touches both) and voila.

  7. #7
    Xtreme Member
    Join Date
    Jun 2005
    Location
    Oregon , USA
    Posts
    435
    Just take the stock CPU coller and cut it up and use as adheisive

    Warning : As-Adheisive Is perminate
    also make sure to have replacement heatsink and wear goggles
    FOLD for XS WCG ; or Rodzilla kills a kitten

  8. #8
    Xtreme Member
    Join Date
    Feb 2007
    Location
    Indonesia
    Posts
    108
    Can u try with aluminium custom...mybe ok...thanks

  9. #9
    Registered User
    Join Date
    Oct 2005
    Location
    Serbia, Belgrade
    Posts
    69
    I just direct couple of airflow from CPU cooler to fet's with peace of cardboard and difference is big, they are not so broil as before, not even hot, they are muggy as I can express like that.
    So, active cooling is helpful, that's for sure.
    In me, still remain question: if I add some heatsinks, will active cooling become unnecessary?

  10. #10
    IT Engineer in the making
    Join Date
    Jun 2003
    Location
    Former Kingdom of Bavaria
    Posts
    2,094
    No, for the reason I already told you.
    Quote from one of our professors:
    "Reality is hiding in the imaginary part."

  11. #11
    YouTube Addict
    Join Date
    Aug 2005
    Location
    Klaatu barada nikto
    Posts
    17,574
    Fast computers breed slow, lazy programmers
    The price of reliability is the pursuit of the utmost simplicity. It is a price which the very rich find most hard to pay.
    http://www.lighterra.com/papers/modernmicroprocessors/
    Modern Ram, makes an old overclocker miss BH-5 and the fun it was

  12. #12
    Xtreme Member
    Join Date
    Mar 2007
    Location
    The Netherlands
    Posts
    199
    nn_step... are you using dice 24/7?!

Bookmarks

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •