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chris000001
07-11-04, 07:51 PM
Not sure this fits under cooling but assumed it did becuz cooling causes air pressure in the case, but anyways i have 4(2 80mm, Psu fan, and slot exhaust blower)exhaust fans and 2(2 80mm) intake fans and you guys are always saying how negative air pressure is good but do i have too much negetive, my case has sloted intakes alog the top so i guess they might add a little more positive presssure, should i add another intake fan or not?
in54n3
07-11-04, 11:45 PM
there intake fans on the top of the case? and also..u can never have too much negitive pressure. if its regular intake fans in the front of the case...id say either use only 1 fan (assuimg theres 2 slots) or use lower powered fans then ur exhausts. if its blowing air into the case from the top....then thats weird ;), ive always heard of blowholes (air blowing out..obviously), not intake.
chris000001
07-12-04, 12:54 AM
This isnt my computer its one i built for a customer its the same case as mine jus black (mine is silver) i didnt have any pics of the slots on mine so i used a pic i took of his while building it.
http://www.chris000001.5gigs.com/karls.JPG
there are slots across the top on mine jus like that on both sides and when i put my finger over the slots i can feel air being sucked in
dantheman
07-12-04, 01:11 AM
I would say your fine as is. The negative pressure inside your case is what is causing the air to go through the vents, and that's a good thing. Like In54n3 said, you can never have too much negative air pressure.
Assimilator87
07-12-04, 02:19 AM
There will still be a difference between ultra negative pressure and even pressure, right? For example [3 Tornados (exaust)] vs. [3 Tornados (exaust) + 3 Tornados (intake)].
Ginsu543
07-12-04, 05:14 AM
It's always better to have more negative pressure (more exhaust than intake).
gokusimpson
07-12-04, 06:30 PM
Colin had a tip on negative pressure didn't he?
Assimilator87
07-14-04, 05:41 PM
It's always better to have more negative pressure (more exhaust than intake).

If that's the case, why do people even bother with intake?
Sadistic
08-08-04, 11:34 PM
If that's the case, why do people even bother with intake?

exactly. Im confused on this one as well. I have 3 in and 3 out (not including the PSU fan which would make 4 out...i guess). If the idea is to create negative pressure then why even bother?

I was always told negative pressure was bad as it tends to suck dust into the case from every single nook and crany.
ElrichMeister
08-09-04, 12:19 AM
im thinking the use of intake fans is to pull in more fresh air into the case, you just need more negative pressure to take it out.
Ginsu543
08-09-04, 02:17 AM
It's not bad to have intake fans, it's just better to have more exhaust than intake. I like having intake fans in the front of my case because they blow air over my hdds, cooling them down.
bluegreenshxt
08-09-04, 04:46 AM
hmm...i always thought the side should be intake...
Avid6eek
08-09-04, 01:38 PM
Negative air pressure in the case allows for a more steady airflow through the case. If you push more air into the case than it can exhaust, it will just make the inside of the case turbulent, and won't cool very efficiently. The reason for air intake is to force the majority of the air that does come into the case to come from the lower front, and it allows air to move more quickly through the system. 5 fans (3 exhaust, 2 intake) will result in better airflow than 3 fans doing all the work (3 exhaust).
c0ldweller
08-09-04, 01:53 PM
Negative air pressure in the case allows for a more steady airflow through the case. If you push more air into the case than it can exhaust, it will just make the inside of the case turbulent, and won't cool very efficiently. The reason for air intake is to force the majority of the air that does come into the case to come from the lower front, and it allows air to move more quickly through the system. 5 fans (3 exhaust, 2 intake) will result in better airflow than 3 fans doing all the work (3 exhaust).

Well said. I used to have 5 intake fans and 3 exhaust (including PSU, but 3 of the intake fans were low level like pushing 20-25 CFM's) and then I just recently switched back to having the side panel exhaust instead of intake and my motherboard temp went down while my CPU temp went up. Weird but it's always good to have a steady flow of air being blown straight across the case. A good example of a case that does this really well is the Cooler Master CM Stacker: 3x120mm intake fans in the front and for exhaust, 1 80mm in the top, 2 80mm fans in the bottom of the rear of the case, and a 120mm fan in the center back, as well as an attachment fan on the side of the motherboard tray that blows air straight across the motherboard. If onlly that case cost $50 :rolleyes: .
TranceJunkieXL
08-10-04, 04:56 PM
If that's the case, why do people even bother with intake?
Haven't you wondered why PC manufacturers like Dell and HP never have intake fans? There's your answer!
LOL! The only time negative air pressure would be a problem would be if the case suddenly implodes. ROFL!
Negative air pressure causes cool air to be drawn in from any nook and cranny. Positive pressure (too much intake) causes turbulence, which means the same heated air is circulated over the components, thereby reducing the effectiveness of air as a method of cooling altogether.
PCgeek
08-10-04, 06:06 PM
Yep, the only reason I use intake fans is to cool my HDD and VC.
Fan should be located in the following manner:
Side, Front = Intake
Back, Top = Exhaust

You always want the air to travel from front to back, and hot air rises so intake should always be as close to the bottom as possible, and exhaust as high as possible.