Fan positioning and positive pressure.

Hi there,
Basically I'll be buying magnetic air filters so I can minimize dust intake and I want to buy the right amount. I have 7 fans at the moment and I'm not sure if they're in the right direction and/or CFM for positive pressure.

I have a case down below which isn't actually mine (I just found someone with an Antec 300 case. Blue arrows indicate air flow.

Fan 1: Intake @ 61CFM
Fan 2: Intake @ 61CFM
Fan 3: Intake @ 37/46/54.3CFM
Fan 4: Exhaust @ 37/46/54.3CFM
Fan 5: Exhaust @ 39/56/79CFM - Antec 300 rear fan
Fan 6: Exhaust @ 47/67/95CFM - Antec 300 top fan
Fan 7: Exhaust @

I have a fan controller which controls Fan 1,2, and 7 so I can adjust accordingly. Help would be appreciated!
7 answers Last reply Best Answer
More about positioning positive pressure
  1. Whoever that case belongs to, sort your bloody cables out!! :P

    airflow you have shown is 'correct', although each case will benefit from experimenting to find the best set up for your situation,
    I would have the most powerful fans as front intakes with the filters you want,
    and the rest as exhaust with no filters
    (I don't class the Heatsink fans as intake or exhaust)
    but filtering fans slows the flow so having the most powerful ones there will compensate and exhausts don't ned filtering as they are pushing out of the case
  2. Haha is that cable management that bad? Mine is similar and I thought it was great. Guess I'll have to redo it.

    I wasn't sure if this is viable to make an effective Positive pressure build. Example being:
    Side fan intake (with a filter)
    Front fans intake
    Top of the case intake
    Rear fan being the ONLY exhaust

    Is this viable or is the ratio extremely high since all the air has to go through the small fan at the back. I'm confused because I was reading here and I saw this animation at Benefit 1 on this webpage

    I've marked this diagram with yellow circles being fans from the power supply and graphics card. They conflict with each other so I'm not sure if I want fresh air to go into the area or to make the heat escape by making it an exhaust
  3. Best answer
    I'm the resident cable management monster here sorry :P
    if I can see cables I get upset hehe
    I'll link a pic if you want to see what to aim for
    have your Psu fan down as in that picture, that means the flow is from outside the case and exhausts out the rear, so it doesn't affect internal flow,
    if you don't have grill in the bottom you can always cut a section out or drill holes there if you wanted to
    if you have the powerful fans as intake and maybe use the fancontroller to lower the exhaust speeds, you should easily attain positive pressure,
  4. Yeah I've found one which looks amazing in my opinion Thanks for the help!
  5. Thats better, still room for improvement but theres no problems with that :)

  6. Best answer selected by majikfx.
  7. Thank you for B.a. man, glad to help :)
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