Passively cooled PSUs/joining them

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What do you mean by combine them? Do you mean physically join them together some how? You should be able to use one psu for the mobo, cpu etc and another for all the hard drives/fans or whatever else you have.
 
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Im not sure myself but I think you will be able to find a guide on the internet somewhere or someone else will know. I assume you know how to start a psu without a mobo? You could probably use some kind of push button switch.
 
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I think theres some sort of splitter that goes into the 20pin socket on the motherboard, so that when the case is turned on.. the motherboard boots up both power supplies.. or something
 
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Firstly to turn a hard drive on you cross two wires in the 20/24pin group (have a guide on computer could email to you). What i would do is setup a switch on the front panel switch so that when you switch it you turn that psu on - then press the power button and motherboard turns on with other psu.
 
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aha kk sounds gd :D and I guess can also use some of the molex from the cpu PSU to power more stuff also?

Though what's the most powerful passive cooled psu's avail?
 
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If it was me id go with 2 tagans. They are very quiet and only really spin up when they get hot but seeing as your splitting the load you shouldnt have any problem with that
 
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I really want PSU's without fans at all thou, I thought they existed? idk =[ this soo much effort! got the mobo, replaced the NB got passive cooled CPU, got silent HD caddies. just need psu :D
 
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ErNciLator said:
there anyway to combine more than 1 PSU easily?
Easily, would be a manual switch to start the 2nd PSU before the 1st powering MB. You could connect a 2nd PSU via a relay to the 1st. I seen where just directly connecting the two doesn't work as expected. Anything checked for by the MB at post, may not be seen. As there may be a bit of a delay on the 2nd PSU start up. This can be over come with a small circuit which will make the MB wait for both PSU to ramp to full voltage. But its not for the inexperienced. I'll stick it here in case anyone does a search for connecting two PSU. It looks worse than it is, take about half an hour to knock it up with some stripboard .

http://www.zittware.com/pc133sdram/info/DualPSU/DualPSU.html
http://www.burningissues.net/how_to/power/psu.htm
 
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Going completely fanless isn't always the best (or quietest route)

Take away all PSU and case fans completely and how is the heat from these passive components going to escape from the case? Without some kind of chimney effect (which i believe requires nearly a 2metre chimney to be effective) some part of your PC is eventually going to get too hot - whether it be northbridge, hard drive or some smller no name component which will eventually fail or cause instabilty. Totally passive can be done, but only reliably with ultra low power components to start with - ie laptop drives / sub 16W CPU etc.

Since this is the case, my philosophy has been to retain the PSU fan but use it to provide case cooling. You can very nicely cool an AMD system with just two 120mm nexus fans (one in the psu one for the case) 5 volted so that they spin at only 400rpm. By carefully considering the airflow in your case so that cool air is drawn in over the hard drive/s you can keep all your components at sensible temps easily enough.

The irony is that unless you do some research first, those passive PSUs may well be louder than my 2 fan system. Quite often these PSUs exhibit a noticable an annoying buzz that is far louder than the nexus fans in my system.

Good luck if you decide to go the passive PSU route, but you might still consider getting an S12 seasonic and swapping the fan for a nexus. (assuming you understand the dangers of opening up a PSU)

Marc
 
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Starting more than one PSU only requires you to connect an earth from each PSU and the green wire (usually) from each psu which is the power on signal wire, then just connect the one motherboard plug and when you hit the power button both will turn on.

Been doing this for over 2 years now and its fine.
 
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Thanks, fornowagain :) iv got some stripboard and solder at the ready, and im having a go later today.

Got 2 x 200w passive cooled PSU's also, thanks all.
 
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marc mercer said:
Going completely fanless isn't always the best (or quietest route)

Take away all PSU and case fans completely and how is the heat from these passive components going to escape from the case? Without some kind of chimney effect (which i believe requires nearly a 2metre chimney to be effective) some part of your PC is eventually going to get too hot - whether it be northbridge, hard drive or some smller no name component which will eventually fail or cause instabilty. Totally passive can be done, but only reliably with ultra low power components to start with - ie laptop drives / sub 16W CPU etc.

Since this is the case, my philosophy has been to retain the PSU fan but use it to provide case cooling. You can very nicely cool an AMD system with just two 120mm nexus fans (one in the psu one for the case) 5 volted so that they spin at only 400rpm. By carefully considering the airflow in your case so that cool air is drawn in over the hard drive/s you can keep all your components at sensible temps easily enough.

The irony is that unless you do some research first, those passive PSUs may well be louder than my 2 fan system. Quite often these PSUs exhibit a noticable an annoying buzz that is far louder than the nexus fans in my system.

Good luck if you decide to go the passive PSU route, but you might still consider getting an S12 seasonic and swapping the fan for a nexus. (assuming you understand the dangers of opening up a PSU)

Marc

Precisely what I'm thinking. I would certainly not feel safe with no fans at all, all that heat just stuck in the case :eek:

Get a big case that will take 120mm fans front and back, you can get pretty much inaudable 120's now. And that will actually keep your system pretty cool as well as silent.

I just dropped my sisters P4 temp from 50 to 40 just by using a bigger case that came with a 140mm in the front and a 120mm at the back.
 
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