Flexible fanduct and noise?

Snakebite · Post by **Snakebite** » Sat Oct 26, 2002 7:20 am

For reasons I won't go into here, I'm planning to place my PSU in the front of my case and not in the regular place in the back. Still the exhause must go out the back, so I was thinking of using a flexible fanduct such as the one seen here. I'd like your opinions on how this might affect noise. Would I be better of building a stiff fanduct with smooth sides out of metal/cardboard/whatever?

GamingGod · Post by **GamingGod** » Sat Oct 26, 2002 8:04 am

i couldnt get your link to work, but i would think that you would get more airflow from a smooth surface, but i would be wary of metal as you could short something out if your not extremely careful.

Red Dawn · Post by **Red Dawn** » Sat Oct 26, 2002 3:59 pm

Hi snakebite, and welcome to the forums!

I have sort of an idea that might work out for you.
What if you would have the fan 'hanging out' (remember to use a dust filter if you do this), blowing inwards, and remove the 'back part' of the PSU case and put in some sort of grill, or equivalent to stop things from accidentally going through the back of your PSU, and then have rear case fans blowing out the hot air?

Only thing I can think of is that having a fan mounted like that might be bothersome if you sit directly infront of your computer, you might want to try and shifting the case sideways or something... like I said, just an idea.

Snakebite · Post by **Snakebite** » Sat Oct 26, 2002 8:29 pm

Thank you for your replies and suggestions. I've already discussed my idea on another forum, but I might as well give you the long story too:

What I want to try is to use only a single 120mm fan to cool the whole computer. CPU, gfx card and maybe north bridge too will be water cooled. I will mount the radiator inline with the power supply, on the side that normally faces the CPU or down in a tower case. The fan will blow first through the radiator and then through the power supply.

I think it might work. Since the major components are watercooled, the air inside the case should be relatively cool. The air coming out of the radiator will be warm of course, but hopefully enough to cool or at least get the hot air circulating out of the power supply.

The problem is, if I put the power supply where it normally goes, there won't be enough room for the radiator and fan. In my desktop case, there would be enough room in front of the motherboard. But the the exhaust from the power supply would be inside the case and I need a way to direct it to the outside - without an additional fan, or my project will have failed.

Red Dawn · Post by **Red Dawn** » Sun Oct 27, 2002 4:06 am

Hmm, interesting... were you planning on running the PSU closed or open in this setup by the way?

I have no experience with watercooling whatsoever, but I suspect (much like you do) that the air coming from the radiator will be quite hot.
You might want to try using a thermalprobe (digidoc5 or the cheap senfu digital thermometer also found at the site you linked to earlier) to watch the effects of this setup, and if needs be; you can always modify it.

Snakebite · Post by **Snakebite** » Sun Oct 27, 2002 4:51 am

Red Dawn wrote:were you planning on running the PSU closed or open in this setup by the way?

I think it's best to run it closed. I will only leave a big exhaust hole where the PSU fan normally is. I'm even thinking of plugging the vents. Since the fan is pushing, the vents won't serve as air inlets anyway and the hot air would escape back into the case.

Another alternative to try is
PSU --> fan --> radiator. But I'd rater risk burning my PSU than my CPU and gfx card.

Red Dawn wrote:You might want to try using a thermalprobe (digidoc5 or the cheap senfu digital thermometer also found at the site you linked to earlier) to watch the effects of this setup, and if needs be; you can always modify it.

Yes, I need stuff to monitor waterflow, fan and tempratures. I'm new to all that. All new motherboards come with pins for attaching these RPM signal cables?

Red Dawn · Post by **Red Dawn** » Sun Oct 27, 2002 5:36 am

I'm not sure I understand exactly how you want to run your PSU, you say you want to plug the vent holes on it? Then how is hot air going to escape? Through the chassis itself? Play it safe, so you'll avoid being sorry in the end, I say.

Yes, I thought about the PSU>Fan>Radiator setup as well, try that later on when you've got everything rolling so to speak, and see if it works adequately.

Snakebite wrote:All new motherboards come with pins for attaching these RPM signal cables?

Yes, the one's you are talking about is those 'whirlie-thingies', basically a propeller to monitor that water is flowing and then reporting a rpm signal through a regular 3-pin connector to the motherboard through a regular fan connector, right? If that's the case, you shouldn't worry, it will work out just fine.

Snakebite · Post by **Snakebite** » Sun Oct 27, 2002 6:33 am

Red Dawn wrote:I'm not sure I understand exactly how you want to run your PSU, you say you want to plug the vent holes on it? Then how is hot air going to escape?

I mean I'll remove the fan that comes with the PSU, that hole will be the exhaust and this is where I need an airduct to lead the hot air out of the computer case.

Then I'll cut open a big hole on the top/bottom of the PSU where the 120mm fan will blow in through the radiator.

All remaining little inlet holes around the PSU will be plugged.

Red Dawn · Post by **Red Dawn** » Sun Oct 27, 2002 7:25 am

Oh, I see. Just make sure the air is flowing out through the duct and not getting trapped inside the PSU. Tell us how it goes, and good luck!

marc999 · Post by **marc999** » Fri May 23, 2003 3:00 pm

Hi Snakebite.

Just reading through some old threads and came upon this one. I like your idea and was just wondering if you found sucess. Would you like to share with us any knowledge you have gained ?