1. Welcome to TechPowerUp Forums, Guest! Please check out our forum guidelines for info related to our community.

cooling: blow more in or suck more out?

Discussion in 'Overclocking & Cooling' started by randomperson21, Jul 25, 2006.

  1. randomperson21

    randomperson21 New Member

    Joined:
    Dec 28, 2005
    Messages:
    1,535 (0.48/day)
    Thanks Received:
    0
    Location:
    San Luis Obispo, CA
    3 pin fan cables/ whatever are usually 12v, right?

    and if the molex fans are running at 12v anyways...
    i could most likely just cut the fan where its coming out of the molex adapter, then solder on directly the red/black wires from the 3 pin. that wouldn't be so bad...

    thanks for all the help everyone!
     
  2. error_f0rce

    error_f0rce New Member

    Joined:
    Jun 6, 2006
    Messages:
    942 (0.31/day)
    Thanks Received:
    12
    Location:
    Wisconsin, USA
    Yup, run red to yellow and black to black. Just make sure to insulate the connection point after soldering (i.e. electrical tape, etc), you don't want that touching anything metal :D

    GL!
     
  3. randomperson21

    randomperson21 New Member

    Joined:
    Dec 28, 2005
    Messages:
    1,535 (0.48/day)
    Thanks Received:
    0
    Location:
    San Luis Obispo, CA
    ha yeah.

    my fans are set up like a molex passthru deal. so if i snip them before they get to the molex adapter, i'll just have the red and black.
    as well as a nifty 2" molex extension cable.....
     
  4. error_f0rce

    error_f0rce New Member

    Joined:
    Jun 6, 2006
    Messages:
    942 (0.31/day)
    Thanks Received:
    12
    Location:
    Wisconsin, USA
    Another option is an adapter. They have some at Xoxide for $2 each:
    http://www.xoxide.com/3to4pinadaptor.html
     
  5. _33

    _33 New Member

    Joined:
    Mar 25, 2006
    Messages:
    1,248 (0.40/day)
    Thanks Received:
    31
    Location:
    Quebec
    I'd recommend to equally push as much air as you pull, that way the air will flow freely and the fans won't make as much noise as they will suffer a little less pressure. A 120mm front and 2 X 80mm back is probably an ideal config. If you got a blower on the side, that's perfect.
     
  6. randomperson21

    randomperson21 New Member

    Joined:
    Dec 28, 2005
    Messages:
    1,535 (0.48/day)
    Thanks Received:
    0
    Location:
    San Luis Obispo, CA
    i calculated the cfm intake and outtake, and its going to be pretty balanced by the time i'm done. roughly 150cfm in and out at 100% power.

    My PSU will add a bit more out, but not much.
     
  7. error_f0rce

    error_f0rce New Member

    Joined:
    Jun 6, 2006
    Messages:
    942 (0.31/day)
    Thanks Received:
    12
    Location:
    Wisconsin, USA
    Very true, pos/neg pressure does create more fan noise.
    As for an equal flow ratio, yes it will increase the rate of flow... however, I would still hold that a negative pressure (however slight/great) will more effectively eliminate dead-spots and trapped heat. Hot air will rise to the top of your case and sit there while the cooler air passes/flows beneath it. Creating a vacuum (neg pressure) will displace the hot air that is trapped up top. Perhaps the exception would be if you had a blowhole, this would free the trapped air as well.

    My 2 cents :D
     
  8. _33

    _33 New Member

    Joined:
    Mar 25, 2006
    Messages:
    1,248 (0.40/day)
    Thanks Received:
    31
    Location:
    Quebec
    Currently I have a very slow 120mm front that blows like 20 CFM. I got a very normal 80mm side intake that probably gets another 30 CFM (it's got a filter). Thoe I got a really fast 80mm in the back that used to be a PSU fan and it's quite effective (maybe 50 CFM). I got another 80mm that's quite less effective (20 CFM approx). I got the AC Silencer 5 rev 2 blowing air out. And finally the PSU is blowing air out.

    I'm a little like what you described. But I think I'll get a stronger 120mm intake.

    With this setup, I can enjoy a 32°c idle / 45°c load on a 1050 mhz overclock, while having ambient temp of 27°c.
     
    Last edited: Jul 27, 2006
  9. _33

    _33 New Member

    Joined:
    Mar 25, 2006
    Messages:
    1,248 (0.40/day)
    Thanks Received:
    31
    Location:
    Quebec
    BTW, you should blow air in from the front, and out to the back, not the other way around. Unless you have something particular you want to do. But the rule is: Cool your hard drives first, and then send that air to the back and out.
     
  10. randomperson21

    randomperson21 New Member

    Joined:
    Dec 28, 2005
    Messages:
    1,535 (0.48/day)
    Thanks Received:
    0
    Location:
    San Luis Obispo, CA
    i figured that too. in my haste to get my computer back together, i mounted the fans backwards.

    i've stripped my case, and i'm just waiting till i can run to the hardware store to pick up a 3" holesaw for a blowhole.
    also going to drill out the front and back grills for better airflow.
     
  11. error_f0rce

    error_f0rce New Member

    Joined:
    Jun 6, 2006
    Messages:
    942 (0.31/day)
    Thanks Received:
    12
    Location:
    Wisconsin, USA
    IMHO, don't use a hole bit and drill for the top, unless you have a drill press. If you do it by hand, that SOB could slip & slide all over the top of your case and scratch it badly. :eek: If you have a jig saw, or a dremel use that instead. Also, whenever cutting a case use masking tape all over where you are cutting/drilling. This not only makes it easier to draw/trace on top of, but if your blade jumps, or you slip, it will ensure you case doesn't get scratched. Also be sure to DENT the case with an awl or something where you intend to drill your case fan mounting holes. This will help the drill bit stay where it is supposed to, otherwise it will also play slip & slide.

    Also I would recommend some type of grill for the blow hole, that seem to be the one that the most stuff tried to fall in :D

    Good luck, be patient, post some picks when you're done so we can see k? :)
     
  12. randomperson21

    randomperson21 New Member

    Joined:
    Dec 28, 2005
    Messages:
    1,535 (0.48/day)
    Thanks Received:
    0
    Location:
    San Luis Obispo, CA
    thanks for the excellent advice, error_f0rce.
    this is my first time drilling a blowhole, so it should be interesting.
    the only reason i was thinking 3" holesaw is that i don't have a dremel, and my jigsaw is about 10 years old.......
    so i'm off to the hardware store this afternoon to see what i can dig up. perhaps i can find a cheap dremel somewhere.

    i heard that putting a little oil down around the area you're going to cut helps the hole saw cut better. true?
     
  13. error_f0rce

    error_f0rce New Member

    Joined:
    Jun 6, 2006
    Messages:
    942 (0.31/day)
    Thanks Received:
    12
    Location:
    Wisconsin, USA
    I'd be carful, the oil might just make it slide around. If you are drilling aluminum, that's a lot easier than rolled steel. If you mask up the top of the case with a bunch of layers of masking tape, that will help a little with the bit staying put. Still would not recommend doing it that way though.

    Maybe you could borrow someones dremel/jig saw? If you use the jigsaw make sure to start the cut with a few drill holes, overlapping eachother. That will let the jigsaw blade get in there.

    Here is my case: that's an 80mm blowhole up top and a 17" tall window on the side
    http://forums.techpowerup.com/showpost.php?p=126533&postcount=316
     
  14. randomperson21

    randomperson21 New Member

    Joined:
    Dec 28, 2005
    Messages:
    1,535 (0.48/day)
    Thanks Received:
    0
    Location:
    San Luis Obispo, CA
    wow nice...

    i emailed some buddies to see if i can borrow a dremel, haven't heard back yet.

    what do you think of 2x80mm blowholes right next to each other? i know with a dremel, you can cut with a lot less vibrations propagating thru the metal. so 2 80mm fans, mounted parallel to each other, with about 2cm of space in between?

    sorry if i'm not real clear...
     
  15. bbriand New Member

    Joined:
    Jun 27, 2006
    Messages:
    152 (0.05/day)
    Thanks Received:
    0
    I don't know if this would work or if it would bend the case but you could try:
    - cut the same size hole in a piece of 2x4 (or 1x4)
    - drill the mounting screw holes in the case and in the 2x4
    - mount the 2x4 to the case with bolts (using the biggest washers you can find)
    - use the hole in the 2x4 as a guide. No slippage (I'd still use tape though).

    maybe even use a piece of 2x4 on the other side of the case. So you would have a 2x4 sandwich with your case as the meat ;)

    In fact using the 2x4 on the other side without a hole in it might be a good thing. If your hole cutter has a mandrel bit (or whatever its called but basically a bit in the center of the hole saw) the wod would also help keep it centered.

    Anyone tried this before?

    Also I remember someone mentioning not to purchase the cheapest hole saw you could. Pay a bit more and they tend to do a better job on metal. The oil would be a good idea too if you can keep the saw from slipping.

    Remember WD-40 is NOT an oil :D

    Good luck,
    Bill
     
  16. error_f0rce

    error_f0rce New Member

    Joined:
    Jun 6, 2006
    Messages:
    942 (0.31/day)
    Thanks Received:
    12
    Location:
    Wisconsin, USA
    As crazy as it sounds, that just might work!! If all you can get your hands on is the drill and have to buy a bit, then you might want to try what Brian said. You could probably pick up the bolts and washers for a buck or two when you're there to buy the bit, and some wood if you need it.

    Nice idea Brian!!
     
  17. error_f0rce

    error_f0rce New Member

    Joined:
    Jun 6, 2006
    Messages:
    942 (0.31/day)
    Thanks Received:
    12
    Location:
    Wisconsin, USA
    Ok I just deleted the other message I posted, got a little confused for a second. It's up to you what you want to do. If you have a 150CFM in and out, then it just depends if you want a negative pressure in your case (which I would recommend). If you put in another blowhole that will give you another 34cfm or so exhaust. You could, it's up to what you want.
     
  18. randomperson21

    randomperson21 New Member

    Joined:
    Dec 28, 2005
    Messages:
    1,535 (0.48/day)
    Thanks Received:
    0
    Location:
    San Luis Obispo, CA
    that sounds pretty good! if i can get my hands on the hardware tonight, i'll try it out.
     
  19. randomperson21

    randomperson21 New Member

    Joined:
    Dec 28, 2005
    Messages:
    1,535 (0.48/day)
    Thanks Received:
    0
    Location:
    San Luis Obispo, CA
    snap! i found me a dremel tool!
    i'm going to pick it up from a friend tonight, then start cutting.

    i'll post pics as soon as i'm done.

    thx for all the help everyone
     
  20. cdawall where the hell are my stars

    Joined:
    Jul 23, 2006
    Messages:
    20,684 (6.95/day)
    Thanks Received:
    2,984
    Location:
    some AF base
  21. randomperson21

    randomperson21 New Member

    Joined:
    Dec 28, 2005
    Messages:
    1,535 (0.48/day)
    Thanks Received:
    0
    Location:
    San Luis Obispo, CA
    ok its been awhile, but i got the mods done.

    drilled out all the fan grilles, 2x80mm blowholes, new 120mm in back, and some other stuff.

    temps went down a ton! booted it up this morning and...
    [​IMG]

    thanks for all your help guys. tpu rocks!
     
  22. cdawall where the hell are my stars

    Joined:
    Jul 23, 2006
    Messages:
    20,684 (6.95/day)
    Thanks Received:
    2,984
    Location:
    some AF base
    good you managed to beat my amzingly stock ultra case i get about 29C-32C for system temp but i am in houston (hasnt been under 100F in a month) but i have
    3x 30cfm in
    1x 30cfm out
    1x 60cfm out (ex. processor fan)
    psu out
     
  23. randomperson21

    randomperson21 New Member

    Joined:
    Dec 28, 2005
    Messages:
    1,535 (0.48/day)
    Thanks Received:
    0
    Location:
    San Luis Obispo, CA
    yeah, its only 60F out today, so thats most likely why.

    i have 2x30cfm in + 70cfm in = 130cfm in
    3x30cfm out + 70cfm out + psu = <160cfm out.

    plus a 120mm cpu fan, 80mm gpu fan, and a tiny whiny chipset fan.
     
  24. pt

    pt not a suicide-bomber

    Joined:
    Mar 11, 2006
    Messages:
    8,982 (2.89/day)
    Thanks Received:
    208
    Location:
    Portugal
    My Aeroengine will have 1x140mm fan with a 45cfm and an exhaust of 120mm with a 60cfm+PSU, i will probabily put my current fans on the side of the case for better intake :D
     
    Last edited: Aug 8, 2006
  25. randomperson21

    randomperson21 New Member

    Joined:
    Dec 28, 2005
    Messages:
    1,535 (0.48/day)
    Thanks Received:
    0
    Location:
    San Luis Obispo, CA
    wow nice
     

Currently Active Users Viewing This Thread: 1 (0 members and 1 guest)

Share This Page