What's the point of intake fans?

Huugs

Huugs

Huugs

Associate
Joined
29 Dec 2005
Posts
93
I'm thinking of getting a new case and wondering if it is better to get fans blowing air directly in over the hard drives and less fans blowing out or just get more fans blowing out and use the negative pressure to suck the air in over the hard drives?

The drives will be in bays with vents but I'm going to be buying fans to replace the stock ones so need to know which to get it for.

Any thoughts?

Cheers
Paul
 
Last edited:
If you have more input fans you get less dust as you have positive pressure.
(thats if you have filters)

With negative pressure it comes through all the gaps and shizz.
 
Plus with mounted intakes you get a focussed air flow, so your single fan pulling air directly over your drives would cool them better than the slower seepage excess exhaust would cause. Think running water down a hot metal plate - run it down a 1" channel in the centre, that channel will stay cooler than running the same volume of water over the entire surface area. Obviously not to scale, but you get the idea.
 
Ok so the dust getting in through the cracks I get but I am considering having the drives mounted in a rack with vents in the front and a filter on it. So majority of air would be pulled in through there over the drives rather than the cracks.

Deadbeat, I'm still a bit confused as surely through conservation of volume, the air that is forced out of the case needs to be replaced so if the vents in the drive racks were the only opening then the airflow would be the same rate whether there is a fan or not as the opening is the same size.

I'm probably over-thinking this but would like to run it with as few fans as possible. I can understand why you would want fans on the drives if there were other intake fans but I'm not planning on having any.

Thanks for the answers so far though.
 
If you only have vents with filters in front of the drive racks in a case which is (excepting the intake/outtake vents) completely airtight, then then yes you could run one outtake fan with minimal dust ingress. However most cases aren't like that, in most cases a rear fan would more likely pull air from other vents nearer to itself (e.g. slight openings around the card slots), also you need to consider that two fans together can be run slower for the same amount of air flow compared to one fan (two fans running at 1000rpm are quieter than one fan running at 2000rpm). On the flip side, if you aren't planning on overclocking and especially if you pick cooler running components, then you'll probably get away with just the one fan, I wouldn't like to vouch for the longevity of the system though.
 
It really doesnt matter, imo positive/negative air pressure is gimmick
the thing about dust only works if pc is on 24/7, soon as you turn it off dust falls in via gravity
in tests the temp difference between negative/positive and distributed pressure is 1/2 degrees
 
You must log in or register to reply here.
Back
Top Bottom