Best position for 120mm PSU/heatercore fan

MoJo-chan · Post by **MoJo-chan** » Fri Jul 16, 2004 4:06 am

Wasn't sure if I should put this in the watercooling section, but it's really about fans...

I want to use a single 120mm fan to cool both the PSU and the heatercore. The PSU already has a 120mm fan in it. Which is likely to work best? The PSU doesn't really need a lot of cooling I think (550W Q-Tec "Big Fan"), especially since it is not anywhere near the PSU and would be getting air at just above ambiant (say, 32C max in summer). I want to run the fan slowly anyway.

I have been looking for suitable ducting for a 120mm fan but so far have only been able to find 100mm ducts. I think a variation of C with a duct might be good.

MoJo-chan · Post by **MoJo-chan** » Sun Jul 18, 2004 6:57 am

No one?

Gnep · Post by **Gnep** » Sun Jul 18, 2004 7:35 am

I have actually been thinking about something similar recently for my next project - more of that in a second.

For you, option A you would surely get a lot of the air only going through the top part of the heatercore?

Option B might work; however introduces another fan.

Option C seems to be the best.

Now on to mine: I am going to build a self-contained wooden box, with one hole in and one out for airflow (the intake filtered), both pointing vertically down. (There is a nice unobtrusive place out of the way (hence reducing noise also) for this about 12" off the floor, and for aesthetic reasons I am limited to only having the in- and out-takes on the bottom - not ideal I know... but still). I want to duct the air through this unit. Essentially deals with most of the heat produced in the computer. Ducted, filtered intake (can use any old material on the inside of the wooden box for this, even carboard...) and then a 120mm fan for the radiator (might separate the two slightly to get air flowing as smoothly as possible), and then the PSU mounted as shown below to exit the air. Will probably use a pair of matched fans both hardwired at 5V for the PSU and radiator rather than leaving the existing thermally-controlled one in the PSU. Here's a pic - any thoughts anyone?

MoJo-chan · Post by **MoJo-chan** » Sun Jul 18, 2004 8:26 am

Interesting idea Gnep. It's given me one too...

The heatercore is as wide as the case (or at least that side of it, it's dual tower thing). The problem is the pipes run out the side so there is no way it can be mounted inside the case until I start cutting. Removing part of the back of the case to allow it to sit right under the PSU (wth a gap for air flow around the fan) might be a good solution. Another possibility might be to run the PSU at 90 degrees to normal orientation with the core next to it.

For your setup, I think a single fan between the PSU and rad should be enough, plus that way you have room either side which reduces fan noise a bit. If you do have a second fan, have it switched so you can engage it when you need it. I find that I can live with some extra noise when I'm playing games but like the quiet when I'm just working.

Gnep · Post by **Gnep** » Mon Jul 19, 2004 3:38 am

Hmmm I will have to play around once I start building this wooden "heat box" but you may be right - just the one fan between the two components in the channel should be OK. It will even be slightly muffled from the outside world if I do it right as well...

MoJo-chan · Post by **MoJo-chan** » Mon Jul 19, 2004 6:47 am

If you are making it out of wood, it's an excellent opportunity to suspend any fans on elastic! I have found it's by far the best way to reduce vibrations.