New project for to decrease temps read on

[Myself and I]

Ok need some oppions after you read this.

I am thinking about createing a duct system from my cpu to the side of my case blowhole. the blow hole is 92mm and the cpu fan is 80mm
now the duct will be compleatly sealed and will be about 7 inches long . if i where to bring in cold air this would decrease temps dramatically. Now the 92mm fan is going to be blowing as well as the 80mm on the heatsink.
get it
tell me what you think

[Legionnaire]

may create some turbulence in the tube, and chances are that it's not gonna help that much. I'd put in a passive duct, and have the 80mm suck the air, and have the 92mm blowing somewhere else.

[Myself and I]

actually my idea is to buy some tubeing and attach it to the 80mm to 92mm blowhole. Then blow cold air onto the 80mm onto the heatsink . the blow hole is on the side of my case .near the floor which is cool.

[ElvishArcher]

I dont know about you, But I'm going to create a stand to raise my comp about 5inches off the ground, make a hole in the bottom of my case, put in a 80mm or 120mm fan, and duct it to my CPU, incase you didnt know, hot air rises, so all the cold air would be on the ground.

[Myself and I]

i dont know about that seems like there would be alot of dust being sucked up
my 92mm blowhole is aobut
3 inches from the ground on the side of my case
i think it would be phat to have some sort of air tight tubing wrapped up with duct tape going to the cpu which would be 80mm
both fans would be blowing about 100cfm of air.
my other 92mm blow hole can blow directly on my pci slots
man i think i found something here

[nikhsub1]

Originally posted by ElvishArcher
I dont know about you, But I'm going to create a stand to raise my comp about 5inches off the ground, make a hole in the bottom of my case, put in a 80mm or 120mm fan, and duct it to my CPU, incase you didnt know, hot air rises, so all the cold air would be on the ground.

That is what I did, sans duct. I put rubber bushings on my cases legs to raise the bottom of the case 1.25 inches and I also use dust covers for the fans. Inside of my case stays clean, only problem is I have to clean the filters every 2 weeks.

[Myself and I]

Ok take that pic of your case and put tubeing from the cpu to a blowhole that about 3 inches from the floor on the side of your case.
have a 92mm for a blowhole sucking air in from the outside straight to the cpu 80mm fan which would also blow on the heatsink
you would have some serious airflow which would be cold and going to the 80mm fan and to the cpu

im going to try it i already have the 92mm blowhole and a 75 cfm fan to suck air in to my delta 80cfm.
150cfm total airflow to the cpu heatsink man

[MadMan007]

I would try the dust with and without the extra input fan. I am betting that you will see a small but noticable decrease with a fan in the duct as well.

You could also try putting some thin cardboard or index card vanes into the duct to make the flow off the 92mm laminar, instead of turbulent. This might help the 80mm out a bit. Just remember to try all combinations, you never know which is best!

One other thing: your logic is a bit flawed in regard to the CFM delivered to the HSF. Fans in series, in your case one in the duct and one on the HSF, do *not* add their CFM together. The 80mm on your HSF acts as the "weakest link" in this chain. In other words, no matter how much air your force into the 80mm, it can only output so much. Since the 92mm will be dropping the air pressure coming into the 80mm, it will help a bit, but it is not equivalent to having a 150CFM fan.

Good luck!

[Myself and I]

but wouldnt the 92mm blowhole bring in the cold air to the 80mm fan?
i think thats the best way to go

[juliendogg]

if you put the two fans in a series in a tube, they are going to be fighting one another, noise levels will increase substantially but i doubt you'll actually get more than a couple more cfm if any to the h\s. the delta (on the heatsink right?) is only going to move at a certain rpm, ditto with the fan in the blowhole. only one of the two is necessary and i'm almost positive you'll create problems, air turbulance, and unecessary noise levels by using both at once. same way the rad fan on a car actually limits cooling of the rad if your doing 90 on the interstate by actually damming up the fast moving air. simple princible. think a little harder and you'll see. you can't move much more than 80 cfm through an 80 cfm fan no matter how much you try unless you overvolt it or something.......


oops. seems madman already beat me to the punch. *L* oh well. two opinions then.....

[diehrd]

Just run duct from heat sink fan to a desired inlet.The heatsink fan will draw all the air it needs from the duct.

Consider ducting from heatsink to case side directly across form heatsink.That way you get a direct flow with no required effort on the fans part.

It is funny I have posted many times how awsom my temps went down with direct ducting.But i figured no one thought it did any good.All of a sudden it seems like a craze or a fad.. he he he

[Myself and I]

OK like you said do it directly to the blowhole from the heatsink using the duct
but should i blow or suck when the fans are on. some people are saying blow is this correct?

[diehrd]

Blow or suck I have it set so the heatsink fan blows down on the heat sink pushing room air directly onto the heat sink.

Then you have to be sure to also intake more room air as well as exhaust all the intaken air,Balance it out.