We all want a quiet system but we all want a cool one too. So when I bought that very hot running Silenx iXtrema Pro 450W power supply (see my warning under "Power Supplies" here http://forums.silentpcreview.com/viewfo ... 0&start=60) and complained to their tech about the heat (38 celsius at idle and 42 under load) he advised me to reverse one of my two rear Panaflo low flow 80mm fans from exhaust to intake in order to create "positive case pressure." At first this seemed to help somewhat but eventually I decided the PSU was still too hot and too loud under load and returned it for a refund in order to buy a Seasonic Tornado 400W.
The Seasonic made my motherboard even hotter! (42 at idle). Needless to say, I was freaking out. Then I thought "Since Silenx sold me a PSU that was neither silent nor cool I wonder of this idea of 'positive case pressure' is baloney too?" So I reversed the Panaflo back to exhaust and my motherboard now idles at 36! What do you guys think about "positive case pressure"?
Positive case pressure (for cooling) - feh!
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Rusty, I'd argue that that statement is also very dependend on the case and how you setup your airflow.
On my Sonata, I reversed the rear fan to an intake, added a very slow spinning 120mm inside the case, just behind the PSU to force some cool air into it and the result is both my CPU and my PSU is running cooler. But I achieved that by setting up a air cycle with a short length and partitioning the rest of the case from this cycle.
I doubt I could get the same results with a 80mm rear intake though so for smaller fan sizes, I guess Rusty's comment would hold true. The 120mm fan does have a large span and access to cooler air.
On my Sonata, I reversed the rear fan to an intake, added a very slow spinning 120mm inside the case, just behind the PSU to force some cool air into it and the result is both my CPU and my PSU is running cooler. But I achieved that by setting up a air cycle with a short length and partitioning the rest of the case from this cycle.
I doubt I could get the same results with a 80mm rear intake though so for smaller fan sizes, I guess Rusty's comment would hold true. The 120mm fan does have a large span and access to cooler air.
Switch the rear fans to exhaust, and open up your intake.
Well, I have both rear fans as exhaust now. So you think the other three Panflos should all be intake? I just reversed the side intake fan to exhaust to see if the temps would drop, but no difference, so I guess only the two rear exhausts are beneficial. Is this what you mean by "open up your intake"?
By the way, I tried replacing my side 80mm low flow Panaflo fan with a 120mm low flow and was very disappointed to find that at anything more than the lowest Zalman fan mate setting it was as loud as a jet turbine. And at that slow speed there was hardly any air flow. So my next question is what is the point of using big fans that are supposed to move the air better if they are inherently louder when they are moving more air?
By the way, I tried replacing my side 80mm low flow Panaflo fan with a 120mm low flow and was very disappointed to find that at anything more than the lowest Zalman fan mate setting it was as loud as a jet turbine. And at that slow speed there was hardly any air flow. So my next question is what is the point of using big fans that are supposed to move the air better if they are inherently louder when they are moving more air?