Just one fan for CPU+PSU?

McF · Post by **McF** » Fri Sep 05, 2003 7:27 am

I've been thinking about it - I have a 120 mm fan sucking air through my cpu HS through a duct, and was wondering if it could be a good idea to use a 90 degrees duct and use the same fan to blow this air through the PSU outside the case - so no fan on the back of the PSU, just one below. Unfortunately I dont have an ATX case to try this out (currently have a desktop mATX).
Anyone tried it yet?

Jan Kivar · Post by **Jan Kivar** » Fri Sep 05, 2003 7:34 am

I'd duct the cold air in from the exhaust fan hole in the back to the CPU HS, and use only a PSU with 120 mm fan (like Fortron, Nexus, SeaSonic) to pull the air through the HS, and through PSU and out the case. Could even work with low wattage CPU.

Cheers,

Jan

Tobias · Post by **Tobias** » Fri Sep 05, 2003 9:24 am

*grin* Not a topic that very many people answers:) I asked the exact same question twp days ago...

I have a 120mm sucking air from the rear opening and an airduct that leads it down over my Zalman6000Cu HS and a much smaller airduct that leads a fraction of the flow down to my zalman-modded FX5600 (which with this setup is 5 degrees less warm than with the efficient and quiet MSI-cooling that came with the card:)

I have taken off the fan in the PSU and am now running it fanless, the only thing pushing air through the PSU in my sealed chassi is the overpressure the fan creates. If it works or not is yet to find out, I fired up the computer only 30 minutes ago...

I guess we will experience in the comming months wether or not it works...

miker · Post by **miker** » Fri Sep 05, 2003 1:12 pm

Only concern would be the increased noise if the fan in the PSU is temp controlled. If the fan in PSU increases too much it may be better to vent the CPU directly out the back instead of through the PSU internals. It depends really on your PSU and your CPU's heat production.

Tobias · Post by **Tobias** » Fri Sep 05, 2003 1:35 pm

I was under the impression that the fan wasn´t in the PSU (the sam way my fan is:) in that case there are no PSU-fan. The only problem I can see is the one dukla2000 made me aware of, that you can´t run the puter with the sides off, since the PSU will not get any airflow.

McF · Post by **McF** » Fri Sep 05, 2003 11:40 pm

you could use the PSU bottom fan OR use your own 120 or 92 mm fan, the place is the same. difference would be that the fan can be manually or thermally controlled by the CPU temp, not the PSU's one.
I came up with this, because I have the fan blowing hot cpu air out of the case right now (through a side hole) and was thinking if this air would be sufficient to cool the PSU if we let it go through it coming in from the bottom and going out the back. Right now it's pretty warm, since I have only one 80x15 mm fan on 5V blowing in the case on my harddrive, and no other intake or out-fans. My PSU is outside the case, with the ATX cable bundle coming in through the hole.
So maybe with a proper intake fan (say a slow 92mm) such setup would be good?

My 120 mm CPU fan is an enermax (no, I cant buy Panaflo in Holland

) turned down almost all the way, AND connected through a Zalman fanmate, so It's probably lower then 5V now. The CPU gets hot, but the fan is quiet - now all I hear is my PSU fan.
Btw - my PSU intake vent holes are muffled with 5mm thick foam (from some pc product packaging), and I tell you - that does take care of the annoying sound produced by the moving air, while hardly slowing it down.
But the fan in it is loud (by Silentpc standards

) - it's a InWin 300W PSU.
Taking the PSU out of the case does help a lot - I did this with my older system, and connected the PSU fan to 5V, and the air or the PSU casing is hardly even warm!