Adding Fan Negative or Positive?

[Just a nickname]

Hello guys and gals!

As I want to improve the air flow of my system, I want to add some fan on it

My case is a CM 690 II and there's a lot of slots to add fans!

I am planning to buy atleast 3 fans, I don't know which yet...

Here's what I was thinking:

The cases fan emplacement

Where I want to put them (forget the #1 [remplaced by one side fan], and the front #2 fan):

So where would you put the fans? By adding 3 fans at these places, I'll have the same amout of push//pull (actually have 3 coming with the case). So which fan would be the strongest the push or the pull for for a neg or posi pressure?

Thanks for any answer & help!

 

[davcon]

I would start with a 140mm in the top possibly two for good measure since heat rises.
1 front intake at the bottom as you indicated and probably another intake on the floor.
Also you want that cooler pushing air out thru the top so both fans should be oriented forcing air up and out the top the 140's would help and are generally quieter then 120's.
Looks like a bottom side panel would help as an exhaust for your gpu i don't know for sure you'd have to experiment.
Btw i own a 690II.

 

[Just a nickname]

I was also thinking at an exhaust side, but it looks like coolermaster disagree, lateral panel is really made to receive intake fans... I'd like to test, but it's damn hard with not plastic pannel as I can't see inside the case.

Also I was confused and I can only put 1 front fan, but you can add one HDD fan intake. Have you seen that fan configuration emplacement? I can't even see where I could put it?!

From what I've read, neg pressure reduce the dead spot as more air is sucked out. So what do you think should I put a stronger fan top and add 2 at either of these location: bottom - side - HDD (if I can find the damn fan emplacement).

 

[J_Sparrow]

Hi,

your picture suggests that your graphics card pushes hot air out of the holes with the red arrows you have drawn. I thought 99.9% of all modern cards suck air in from the case, and blow it out the back of your case? Can you double check. On my 2 x HD5870 set up, i have an http://tech-reviews.co.uk/reviews/akasa-120mm-apache-fan/ drawing air in and pushing direclty over the cards, so my graphics card get fresh cool air from outside the case, it also helps cool motherboard and ram etc.

I also have air coming in the front of the case, one huge fan at the top blowing hot air out.

The biggest difference is that I have my CPU heat sink http://www.hardwarecanucks.com/forum/hardware-canucks-reviews/34658-cooler-master-v6-gt-cpu-cooler-review-11.html in sideways, so it sucks air from the case, (pull/push with 2 fans) over heat sink and into the back case fan (another apache) which is set to blow air out of case.

I have my 920 at 3.80GHz, and when playing games or even prime95 testing, i never get any heat problems.

I realise the apache's are not the most powerful fans, but the are virtually silent. they also have the easy install rubber things instead of screws and so cushion the fan with rubber so it does not directly touch case. It certianly helps with keeping them silent.

 

[Just a nickname]

The card expulse most of the hot air outside, but I still can feel hot air coming from the card inside the case (which sucks). It's not that huge, but when you try to have the lowest temp I guess it is something to take in consideration... So a side fan would probably solve that problem!

Still can't find the damnit HDD fan emplacement. Why is their explanation so crappy, can't find a damn system with that fan config too!

 

[davcon]

I was also thinking at an exhaust side, but it looks like coolermaster disagree, lateral panel is really made to receive intake fans... I'd like to test, but it's damn hard with not plastic pannel as I can't see inside the case.

Also I was confused and I can only put 1 front fan, but you can add one HDD fan intake. Have you seen that fan configuration emplacement? I can't even see where I could put it?!

From what I've read, neg pressure reduce the dead spot as more air is sucked out. So what do you think should I put a stronger fan top and add 2 at either of these location: bottom - side - HDD (if I can find the damn fan emplacement).

http://www.coolermaster-usa.com/product.php?category_id=19&product_id=2971
Dude! just add one or two 140mm at the top for sure it's imperative for airflow.position# 1
As for then side panel fan it will mount as intake or exhuast depending on the way you mount it.position#5
The front 120mm vertical intake installs on the back of the hdd cage you removed.position#7
The hard drive cage mount #7 will cool your gpu as effectively as a side panel mount.
I know cuz that's where i have mine mounted and i tried it on the side panel.
I didn't like it on the side panel as an intake cux it sucked in too much dust(no filter).
My only other suggestion is to try one in position #4 cuz it makes sense to intake air from the bottom.
To wrap it up i would add 2 140mm top exhaust #1 and one #7 intake.
Download some temperature monitoring apps.
GPU-Z for your gpu.
HWMonitor for complete system.
RealTemp for your cpu.

 

[Just a nickname]

Oh well... I tried to reuse the intel fan as it seemed to have the good dimensions to go onto the VGA holder (behind the mobo). The fan is too tall so I can't clip the pannel... Hard work for nothing ;(

I'll just put a dust filter on the side pannel and put my beautiful reused intel fan xD

Anyway thanks for help & advice I finally figured out what the heck was that HDD fan

Edit: I have currently 3 Fans - 1 top (#1), Rear (#3) and front (#2). So that's 1 intake and two exhaust so I guess this is a negative pressure actually!

What I am thinking is adding 2 intake (2xbottom (#4) or 1xHDD (#7) and 1x bottom OR 1xBottom and 1xSide) and one top to fill the left space. So I'd have 3 intake and 3 exhaust. The top one would be more powerfull than the other intake so the pressure would be a bit negative. Is that a good setup?

 

[J_Sparrow]

the 3 in and 3 out or 2 in 3 out both sound good. plus you can pay anyhting form about £3.00 to about £15 for a fan, some are very fast, some make sure there is no dead air zone directly being the motor, some are silent etc. So look into those options. My own personal 120mm is the Apache i mentioned earlier. Its next to silent. But check out a few reviews cos there are other fans like yate loons etc, that are supposed to be awesome, but i've never tried one so cant comment.

-edit- Dude, use smaller photos next time, its a pain scolling down those giant photos, i was on the moon earlier and could see them from there!! O)