Sign in with
Sign up | Sign in
Your question

Air Duct From CPU heatsink to case back?

Last response: in Overclocking
Share
Anonymous
a b à CPUs
a b K Overclocking
May 22, 2002 9:30:30 PM

Has any of you tried to make an air duct from the CPU heat sink to the back of the case, where a 80/120 mm fan sucks the air out?

If so what's the effect, good?, awesome?

and how big is the difference between airflow being orthogonal or parallel over the heat sink?
May 23, 2002 1:13:36 AM

Hey S,

For this to work, you have to reverse the HS fan from blowing to sucking(and most likely add a fan or two to blow, with more ducts with cool fresh air from the front of case). And Yes I do believe it would work! But no I have not tried it.

I have thought of the same idea as you have, and I have often thought of making my own custom case just to house the cooling system. In the end, the lazy side of me wins, & I have decided to leave everything as is, and just upgrade key components. Good Luck with yours.

Peace out...........tile

god knows your entire system setup & he would answer your questions if he could just stop laughing
May 23, 2002 9:55:18 AM

I did something close to this; an exhaust fan on top of the case, just some ten centimeters from processor. I didn't put in any ducts.

Before the exhaust fan the temps were CPU 60+ C and case 45+ C (idle). With the exhaust fan temps dropped almost twenty degrees on CPU and about fifteen in the case. I'd say that the result was good. But, I had high temps to begin with!

You need a good airflow to the heatsink, though. Later modifications, including a new PSU, have hampered this inside my case, and the exhaust doesn't work that good any more. It's water for me, next... Less noise, too.



EARTH.INI corrupted, cannot find GOD.SYS. Reboot universe? (Yes/No/Ignore)
Related resources
May 23, 2002 11:55:00 AM

a blowhole (the method you used -hole in top) is reported by many to have a good effect on cooling. As for ducting, this has also been done before, but normall blowing ON to the cpu- anyway, give it a go both ways, but be sure to let us know the results!!
As for water, <A HREF="http://www.calvsplace.cwc.net" target="_new">my project</A> may give you an idea or two.


If they squeeze olives to get olive oil, how do they get baby oil?
May 23, 2002 3:08:17 PM

I have never do it before but it wouldn't be hard to do.

Here are a few comlications that you might encounter.

1. Just like someone else said before, depending on the heatsink you are using, most have the best results by using expulsion. This is where the air is being directed onto the heatink. Induction is what you would need to do and depending on the heatsink this could raise the CPU temps by 1-4 degrees C. (This what the result is on the Alpha 8045.) What Heatsink are you using and what CPU?

2. How are you going to pipe it to the back of the case? That could cause problems with trying to cool the rest of the case. Especially the graphics card. What card are you using?

Here are some alternatives that you could use in this project...

1. Instead of venting to the back of the case, why not to the side pannel? You could use a clothes dryer hose. This could be attached by pull ties, dyer hose clamps, etc. You could even use a 92mm or 120mm to help exaust the air out of the case.

2. Instead of venting away from the heatsink, why not vent it in using the setup above only in reverse fashion? You would then have external and probably much cooler air hitting the heatsink instead of warer air from inside the case being drawn across the heatsink.

Back to you...

<b>"Sometimes you can't hear me because I'm talking in parenthesis" - Steven Wright</b> :lol: 
May 24, 2002 7:11:02 AM

Hey, thanks for the tips, CALV! Can't make that underground tank, though; I live in an apartment.

One of my concerns has been thermostatic control: at what point should I increase fan speeds. If I set it too low, they're always on at full (=noise), and if they're too low, CPU gets hot. I think I'll settle to a manual control to start with, and do the control electronics later on.

The whole things going to be an independent unit, with fans, pumps, power supply, tank, radiator and the said control electronics.





EARTH.INI corrupted, cannot find GOD.SYS. Reboot universe? (Yes/No/Ignore)
May 24, 2002 10:14:24 AM

I think I'd do it manually as well, to start with. Good luck with the project, be sure to keep us informed as to how you are getting on !


If they squeeze olives to get olive oil, how do they get baby oil?
May 24, 2002 5:18:41 PM

We have a Dell OptiPlex GX110 here at the office, and it has a duct like what you are looking for. I haven't been able to hunt down any third party ducts out there that have a similiar design. I would take a pic of it if I had a place to post it. It seems that Dell has removed the links to this system off of their site, but here are some pics (albeit poor) of the inside of the <A HREF="http://www.dell.com/us/en/dfh/products/chassispopup_dim..." target="_new">Dimension 4300</A> and others. You can barely make out the <font color=green>green</font color=green> duct on the left. It takes the air back to one of the rear fans (though they are not installed in those pics) where it is exhausted from there. Pretty nifty idea.

I also like the way their PSUs are on a hinged platform that swings out of the way when you work (if you don't have a taller tower).

I didn't have a chance to read all of the other posts, but I hope you find something that works for you.

VSP

<i>Upon the occasion in which the defecation comes into contact with the oscillating ventilator.</i>
!