Self spinning fans

Soldato
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Interesting scenario.

I have two 12cm case fans at the front powered by the mobo pulling air in.

One 20cm and one 12cm powered straight from the PSU pushing air out at the top/back.


An energy saving program on my computer was set to lowest power consumption.

It shut off the case fans being powered by the mobo and dropped the cpu fan to low speed.

The 20cm and 12cm pushing air out of the case carried on at full speed because they were manually regulated on a cable from the psu.

The 12cm fans at the front which were powered off... keep on spinning from the airflow being drawn in by the other two fans :D

Thats some sweet airflow :cool:
 
Associate
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Nice!

For the sake of noise would it not be better to have them all spinning a little rather than 2 off and 2 at full tilt though? That might be just me though, I'm very, very picky about how loud my setup is.
 
Soldato
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The 12cm and 20cm exhaust fans are on manual switches from the PSU fixed to the case, informative settings of low, medium and high :)

20cm is always on high because it doesn't really make that much noise, I think most of the noise it does make is down to the huge amount of air it moves through the grill. Only does 800rpm max.

12cm is medium normally because it won't start on low voltage o.0 and I think it does nothing worth having on low. So medium it is.


For normal use all fans are at medium. Too much of a turbine with everything at full blast.

Mind you the worst of the lot isn't the case fans. It's that stock P55 intel cooler.


Everything on low and it just makes a quiet hum which is dwarfed by the occasional electrical squeak and gurgle from the rest of the electronics and HDD.


I'm going to set up the exhaust fans to be controlled by the motherboard at some point too. Swapping between 4ghz and full speed fans to 1.2ghz and extremely quiet fans at the touch of a button while using the computer = win.

4ghz can wait for that H50 though.

Amazing programs with this mobo. Beats using manual fan controls and overclocking from the bios :)
 
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That sounds pretty good to be honest. My PC is in my room so if I'm downloading anything I like to leave it on overnight, the trouble is I have to have it almost silent then. That involves restarting PC, switching to my underclocked BIOS settings, disconnecting all but one case fan and one of the fans on my rad and setting those 2 fans to 5v, then finally downclocking my GPU to minimum so it runs passively.

I'd much rather just push a button :p
 
Soldato
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epic air flow! i've just realised i can mount some 140mm fans on the mobo side of my hard disk rack, very tempted to see if i can get some in there to keep noise down :) (my pc is already pretty quiet, but there's always room for improvement right :D)
 
Soldato
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Seems I can't get positive pressure even with both 120mm intake fans on full and the 120mm+200mm exhaust fans on low.

Notable negative pressure when the exhaust fans are on full. But since the exhaust fans were all that came with the case and the fans assisting intake were optional, guess it's meant to be a negative pressure case.

Does make me wonder how useful the dust filters are when the negative pressure means every grill is now sucking air in ESPECIALLY the ones without a restrictive air filter.

I suppose I could disable the exhaust fans if I really wanted but meh, it cools. I'll just have to dust the inside.
 
Soldato
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I have always been fascinated by people spending mega bux to silence their PC.

My TT Armor PC is running 2x120mm and 2x92mm on the case.
The CPU is a Titan Vanessa - also cooled by a 120mm and the GFX is a Palit 295 with the stock cooler and the PCU is an OCZ and thats got a 120mm inside it.

It has 6 HDs and 4 DVDRW Drives and runs 24/7

The ammount of noise that comes from it, is...

Nope, absolutely silent.

Hang on, I will put my ear to the side of the case, and....

Hmmm.... I think I can hear a slight noise of the wide through its bits, but apart from that....

The noise is roughly about the same as a single cheap and nasty 80mm fan thats held in your hand... Its not completely silent, but if it wasnt for the fact that the PC lights up blue, you would swear its off.
 
Soldato
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That certainly doesn't seem likely to be silent to me. Different sensitivity to noise, that's all.

Are you referring to my PC or ?

Mine is completely silent yes, and its not a different sensitivity to noise at all.

The fans are all silent, and the HDs make no noise, even when they are workign away, its silent and oyu really have to listen very carefully with your ear pressed against the case to hear anything at all, and even then its only a mild hum that most people cannot hear even then!
 
Soldato
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Silent is all very relative.

Mine is a sound reducing case and I know it's never going to be silent to me. But I'm not bothered.

If I'm working the system autoclocks itself to 1.4ghz, turns off the case fans and has the CPU cooler on low. That's pretty quiet.

If I want to game then the system autoclocks itself to 3.5ghz, turns on the case fans to high and gets some air shifting. Still less noisy than a handheld fan. Matter nothing at all because I play with earphones and case hum is inaudible.

I'm not talking about Turbo mode on the i5's mind you, that's disabled, program called EPU-6 doing this for me :)
 
Soldato
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Silent may very well be relative, but that does not sway from the fact that no one can hear it at all unless they press their ears against it.

And mine does not clock itself down either, its running stock speed and Im folding on all 4 cores so its at full speed 24/7

But, I also have my No2 PC and thats not too different to this PC and that too is totally silent, and that case is only a cheap and nasty Icute one... That has 4 HDs, 2 DVDRW Drives, CPU Cooled with an Artic Freezer and CPU is only a generic cheap job, but again, absolutely silent.

In both these PCs, I never went out to make them silent, they just happened to be silent.
 
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